A detailed guide on how Rubick' Spell Steal interacts with all other spells. The article contains tips on stealing and using each skill of agility-based heroes.

Today, we will talk about the interactions with the spells of all agility-based heroes.

Click here for the STR spells!

Many thanks to Geffoo, who did an amazing job testing first-hand all spell interactions and presenting his recommendations.

Anti-Mage

Mana Break

Passive Ability. Unstealable.

Blink

Free Blink at a low cooldown and mana cost which can't be cancelled by damage.
Can substitute the Blink Dagger for a good portion of the game if you do not need desperately the mobility.
Very often the last spell Anti-Mage has cast.
Be warned that occasionally you may get Mana Void, so make sure to have a contingency plan if you can't use the Blink to get out.

Spell Shield

Passive Ability. Unstealable.

Mana Void

Niche Spell that is hard to use well without putting yourself in a lot of danger.
Only really worth stealing if the opponent team has a hero with a large mana pool (Invoker, Storm Spirit, etc.).
Only obtainable in the middle of a team fight.
Can be useful to cancel TPs if everything else is on cooldown.

Notes

Be careful when stealing from Anti-Mage later into the game, if he has a Skull Basher or Abyssal Blade, as he can just Blink and kill you.

Since the Aghanim’s is so popular on Anti-Mage now, you may need to break the Spell Shield with a spell or item. Warning: you cannot use the Blink Dagger to get out if you use Fade Bolt to break Spell Shield!

Arc Warden

Flux

Good slow and a high damaging DoT
Relies on your target being isolated by at least 225 AoE, does count neutral creeps.

Magnetic Field

No difference with the enemy spell. There is no 'Miss!' text that pops up when attacked while standing in the Field, so make sure your allies know which is yours,
Throw enemies out of Magnetic Fields as you generally want them to no be inside.
Active Magnetic Fields do not instantly disappear if the spell is lost or replaced.

Spark Wraith

The is no way to tell the difference between a Spark Wraith cast by you or Arc Warden, only that your Spark Wraith will provide your team with 300 AoE ground vision.
No longer purges targets hit.
Any active Spark Wraiths do not instantly disappear if the spell is lost or replaced.

Tempest Double

Arc Warden's Tempest Double can be stolen from.
Steals the last spell the double cast even if it was from a previous cast of Tempest Double. This occurs since only one double per hero can exist at a time: the new casts replace the old double.
Your Tempest Double cannot steal spells.

Notes

Interestingly, you cannot create an enemy Arc Warden with the -createhero command.

Bloodseeker

Bloodrage

Effectively identical to a Bloodrage cast by Bloodseeker himself, only you have the control on what it goes on.
Can be dangerous to apply to your carry if he gets focused, but generally safe if placed on a long range caster/attacker (Zeus, Sniper, Storm Spirit, etc.).
Decent for Rosh attempts to amplify your team's damage. Also reasonable fire-and-forget spell to apply to yourself if your positioning is good.

Blood Rite

Large AoE silence which has a long duration and does pure damage.
Extremely useful in a team fight or a Roshan fight, and can be very disruptive.
Gives ground vision when charging so can be used to mitigate the Fog of War, but make sure that the centre of the Blood Rite is on the high ground or across the treeline to give you the vision.
Be warned that there is no way to tell the difference between a Blood Rite cast by you or Bloodseeker, and most people avoid the Rite like the plague, so make sure your team knows you have the spell before you cast it.

Thirst

Passive Ability. Unstealable.

Rupture

Great gank tool in the early-mid game when it still does a lot of damage.
Very easy to steal and see coming due to the long windup when cast. If ruptured by Bloodseeker, you can usually instantly steal it and cast it back on him, resulting in a standoff.
Later on in the game, if you have the Aghanim’s Scepter you will get 2 charges, and both charges are given upon stealing the spell. Note that you have to replace or lose the original instance of Rupture to gain the charges back.
Charges Bug: if you cast both charges of Rupture, the spell goes on cooldown until a charge is gained. However if you replace the spell and steal Rupture again, you get both the charges back, but the spell remains on cooldown from the last cast, even though you have charges.
With 7.06, the mana cost of Rupture is substantially higher than before, making it often hard to cast in conjunction with other spells, so be wary of your mana pool when playing against Bloodseeker.

Bounty Hunter

Shuriken Toss

Decent short ranged nuke which can be useful for finishing off kills or cancelling teleports.
If enemies are tracked, your Shuriken Toss will bounce to them, and will bounce twice if multiple heroes are tracked and you have the Aghanim’s Scepter.

Jinada

Passive Ability. Unstealable.

Shadow Walk

Invisibility spell which can be useful for scouting.
Can be stolen during the fade time when cast by Bounty Hunter.
The spell can be replaced during the fade time of Shadow Walk without breaking the invisibility.

Track

Great spell for countering Bounty Hunter himself negating Shadow Walk.
Long cast range now allows for very easy use.
Can be used multiple times to Track the whole enemy team, and as soon as the team fight starts you can discard the spell for something more impactful.
Can be extremely good for speeding up your farm.

Broodmother

Spawn Spiderlings

Decent nuke which will spawn spiders for you.
You cannot have Webs up on the map, so they cannot stack and are always visible.
Be careful when pushing with them as to not give too much farm away.
Good for farming neutrals with. If fights break out elsewhere, you can split push decently.

Spin Web

Niche spell which can be used as a small escape mechanism up cliffs.
Only 2 charges are given upon stealing Spin Web, not all of them.
Free pathing is granted instantly when entering a web.
Webs dropped by you do not affect Broodmother or her spiderlings/rites, webs dropped by Broodmother also do not affect you or your spiderlings/rites.
All webs you created are instantly destroyed when Spin Webs is lost or replaced.

Incapacitating Bite

Passive Ability. Unstealable.

Insatiable Hunger

14 seconds of slightly increased damage and some lifesteal.
Decent for pushing towers and refilling health after a fight, but otherwise pretty much useless.
Since Broodmother is rarely in a fight, it is unlikely you get this spell while being also on low HP. Losing or replacing Insatiable Hunger while activated does not make the buff disappear immediately.

Clinkz

Strafe

A buff that isn't particularly useful for Rubick though can be used for slightly more DPS against towers.
Look out for the small animation of fire that plays when Clinkz uses Strafe as to not steal it.
If Strafe is lost or replaced, the buff does not end immediately.

Searing Arrows

Autocast (Orb) ability. Unstealable.

Skeleton Walk

Nice invisibility spell that also gives bonus movement speed. Allows for rapid scouting, warding, and bounty rune stealing.
Can be replaced in the fade time without losing the buff, but you have only 0.6 seconds so be careful. Be watchful for sentry wards too.

Death Pact

Good temporary HP increase tool, which also results in higher damage for tower pushes and farming

Notes

Be wary of stealing from Clinkz because if he has mobility tools like Hurricane Pikes or lockdown items like Scythe of Vyse or Bloodthorn, he can quickly kill you if you aren't careful. If you want Skeleton Walk, it is best to set sentry traps as he will be invisible when spotted.

Drow Ranger

Frost Arrows

Autocast (Orb) ability. Unstealable.

Gust

Long AoE silence which also serves as a tool to create space between your team and the enemy.
Easy to steal, and as a result is fairly reliable to get whenever you need.
Good to combo with Telekinesis to throw enemies up cliffs to get them off of you. Niche warning: if you are standing in the exact same unit as the target (if they are affected by Telekinesis or either of you are phased) they will not get knocked back.

Precision Aura

Global passive aura, grants bonus damage to allied heroes based on your agility, not Drow's.
Only stealable when Drow Ranger activates Precision Aura to affect ranged creeps too. Casting animation is very small, so it easy to steal accidentally.
No too impactful. Rubick has about 30 Agility at level 11, which adds 6-12 damage depending on the skill level.

Marksmanship

Passive Ability. Unstealable.

Ember Spirit

Searing Chains

Good single target disable that also does a good chunk of damage.
Not great for chasing heroes due to Rubick's below average movement speed. Best when immediately comboed with Telekinesis unless your team has other slows for you to catch up.
Can be slightly hard to hit with its 400 AoE search radius, but with the Blink Dagger it becomes much easier.
If the enemy is standing in a creep wave, you can use Telekinesis to throw him out, into you, and into Searing Chains.
Also a decent neutral farming tool.

Sleight of Fist

Niche skill that does little damage, but can effectively increase your cast range by the range of Sleight of Fist as all spells can be cast while attacking units. However, targeted skills like Fade Bolt or Telekinesis are hard to combine with Sleight of Fist.
The spell can be replaced during Sleight of First and all remaining attacks will complete.

Flame Guard

Long duration AoE DoT which also serves as a magic damage shield. Not as effective as on Ember Spirit as farming creep waves is not as easy with Rubick. Damage block can be a life saver in ganks and team fights though.
Good fire-and-forget spell. Decent to farm jungle with, but you take a lot of damage from neutrals, so only worth it if you have a lot of regen.

Activate Fire Remnant

Given with Fire Remnant. Stealing either Activate Fire Remnant or Fire Remnant will grant Fire Remnant.

Fire Remnant

Good way of safely farming with an escape plan. Comes with 3 charges which are always granted upon stealing, but if all 3 are used then the spell will go on cooldown, which carries over into the next Spell Steal (Charges Bug).
Decent to use as a nuke if you throw all 3 spirits onto a target since you can get all the charges back very quickly.
Also a good chasing tool though the mana cost stacks up fast.
Bonus: the remnants are sweet Rubick models.
Any Fire Remnants left over from previous stolen instances disappear once the spell is lost or replaced (though the animation for the remnant stays bugged).

Faceless Void

Time Walk

Short range escape/initiation tool, great for going over ledges and cliffs, decent chasing tool as well.
It almost always has a much shorter range than you think it is, so be careful and make sure to not click the opposite side of the cliff to mess up pathing.
You are less farmed than a Faceless Void, so be careful of your HP pool, and try to not be too greedy with Time Walk.
Can also be somewhat used to farm jungle and get some HP back.

Time Dilation

A small AoE slow around you. Now has an effect only if the target's skills are already on cooldown, so timing is important. Because of this, it is now much easier to steal both Time Walk and Chronosphere as Faceless Void players are generally much more conservative with Time Dilation.
A difficult spell to use. You need a good timing, and the small AoE can get you killed.

Time Lock

Passive Ability. Unstealable.

Chronosphere

Large AoE disable which affects both allies and enemies.
Usually quite easy to steal, since Faceless Void will Time Walk in or save it to get out, and won’t always cast Time Dilation. Just be careful to not be caught in his cast. It is usually quite obvious when he is about to cast it, so try to stay away until it is used.
Be careful to not trap your own teammates in the Chronosphere.
There is no way to tell the difference between a Chronosphere cast by you or Faceless Void.
Warning: your Chronosphere won’t disable Faceless Void, he will not get the increased movement speed though. Because of this, it is not actually that effective against Faceless Void himself, so it is better to drop it on the backline of supports and casters.
Also, you are not immune to Faceless Void's Chronosphere.
It is generally impossible to help your team if they are already caught in the first Chronosphere, except for dropping another one on the enemy team.

Gyrocopter

Rocket Barrage

High DoT, short ranged skill. Can be used to farm neutrals if you kill the small creeps first, so all the rockets will hit the big one.
Good when used in combination with Telekinesis.
Nice for pickoffs, but the small AoE is dangerous to use in team fights.
It has a very small cast animation, so it is much easier to steal if instead you listen for the sound effect.
Losing or replacing the Rocket Barrage does not cause the spell to end instantly.

Homing Missile

Maxed last on Gyrocopter, and not used as frequently as his other skills, so rarely stolen.
Does a significant chunk of damage if maxed and at long range.
Is somewhat disruptive in a team fight as it is difficult to tell whether the Homing Missile is yours or Gyrocopter's - the only way to find it out is by the health bar and the targeting symbol above the enemy's head.
Rockets already cast are not instantly lost if the spell is lost or replaced.

Flak Cannon

Attack modifier which causes your attacks to hit all units in a large range.
Your damage is not good though, so this spell does very little if any. The six attacks given aren’t even great for farming creep waves.
The cast animation for Flak Cannon however is very small, so it is easy to steal it accidentaly. If that is the case, can be used as a fire-and-forget spell.

Call Down

The most impactful spell from Gyrocopter: a large AoE nuke and slow which lasts for a decent duration.
However, the short cooldowns and low mana costs of Gyrocopter's spells mean that each cast of Call Down is generally followed by many other spells, making it hard to steal - particularly because of the lack of cast animations from Rocket Barrage and Flak Cannon. Cast range is also quite large, so it is difficult to be in range when first cast by Gyrocopter. That said, when stolen is very useful as the slow goes through BKB.
Allies can see the large red target when you cast Call Down though many people will not remember that it cannot be seen by enemies and will think it's not yours. Probably you should warn them.
Regardless of who has the Aghanim’s Scepter, you can never get a Side Gunner.

Juggernaut

Blade Fury

Fairly high damage DoT that also grants magic immunity.
Depending on the game state, it can either be maxed first or last, though Juggernaut is often far ahead in levels. Good for farming creep waves, but less convenient for neutrals as you take a lot of damage.
Decent for pickoffs if your team has a slow - your below average movement speed means that enemies can often outrun you.
Items can be used while casting Blade Fury, so you can save yourself using Blink Dagger or Force Staff if needed.
With the 7.07 QoL change to Blade Fury, allowing Juggernaut to cast healing ward, you can now cast any of your spells while spinning, making the spell much better than before.

Healing Ward

Large AoE heal with a very long duration.
Extremely good for pushing and for after-fight healing.
Great fire-and-forget spell as the ward persists if the spell is lost or replaced.
Allows you to somewhat farm neutrals though your damage output against them is quite low.

Blade Dance

Passive Ability. Unstealable.

Omnislash

Dangerous spell to steal as it can be a death wish to get too close to an Omnislashing Juggernaut.
Stand far away, preferably blink in after it ends, though you need to be quick as they commonly either Manta or cast Blade Fury upon completion.
Despite your poor damage, at level 15 you still do at least ~810 physical damage assuming a level 3 Omnislash.
As a bonus, you can't die during Omnislash, and you can use items like Glimmer Cape to make sure you are safe when it ends.
You can also Blink either right as Omnislash ends or during the Omnislash if you spam click the Blink Dagger.
You can cast any of your other abilities during Omnislash, so you can lockdown or burst enemies. You can even cast Spell Steal, steal a new spell, and cast it during the duration of Omnislash without ending it
Omnislash also uses any additional attack modifiers you might have stolen previously, e.g. Flak Cannon, though only for the auto attacks in between Omnislash hits.
Hilariously, whilst Juggernaut cannot cast Omnislash while spinning, you do not have this restriction. The spin’s damage still works.

Lone Druid

Summon Spirit Bear

Allows you to summon a Spirit Bear though yours cannot cast Savage Roar.
Gains Return, Entangle, and Demolish at the same skill levels as Lone Druid's Summon Spirit Bear.
Spirit Bear instantly disappears if the spell is lost or replaced, but this will not trigger the pure damage.
Any items currently held by the Spirit bear will be dropped if the Spirit Bear dies or disappears because the spell is lost - Do not give him any item!
Even with the Aghanim's Scepter the Spirit Bear will not persist after death as the spell is lost.
Interestingly, neither Lone Druid nor Rubick's Spirit Bear can entangle each other.
Bears cannot be targeted by Spell Steal.

Rabid

Small steroid buff which increases movement speed and attack speed.
Buff is not lost upon cast so can be used as a fire-and-forget spell.
Animation isn't large so can be hard to spot, listen for the sound effect instead.

Savage Roar

Small AoE disable which causes enemy controlled units to run away towards the fountain.
Extremely disruptive, though hard and dangerous to utilize in a fight as the AoE is very small.
It cancels teleports and is nice for getting enemies off of you. Does not affect units in a Duel.
When interacting with other forced commands - Winter's Curse and Berserker's Call - the spell which is cast most recently takes priority.
Note: A unit affected by Savage Roar, who is then Berserker's Called, will not perform any attack until Savage Roar expires.
Cannot be stolen off the Spirit Bear.

Battle Cry

It is not granted with True Form.
When activated, will buff all nearby units under your control, including illusions, Manta, or otherwise summoned units.
The radius is quite large, so it is easy to hit.
It gives some damage and an extremely large amount of armour, and the buff is not lost upon losing or replacing the spell, so it is a great fire-and-forget spell.
There is a small bug which occasionally prevents stealing Battle Cry. When it occurs, it takes one of your skill slots away (D or F) and does not give you the spell. The spell slot is given back upon the Spell Steal buff expiring or being replaced.

True Form

Both True Form and Druid Form can be stolen to get True Form.
Does not persist if a new spell is stolen while in True Form. You also do not get Battle Cry.
The 1.933/0.8 second transformation time (True Form/Druid Form) is also present on your casts.
Will trigger on-cast effects (Essence Aura, etc.)
You lose movement speed, which isn't worth the HP increase.

Luna

Lucent Beam

Long range, decent damage nuke which has a short disable to cancel teleports.
Easy to steal.
Can be used to somewhat farm neutrals though the mana costs adds up fast.

Moon Glaive

Passive Ability. Unstealable.

Lunar Blessing

Passive Ability. Unstealable.

Eclipse

Big ultimate that inflicts a lot of damage. You will learn to love the big purple circle in your skill HUD.
Extremely good if stolen, and since Luna's cast animations are quite significant, it is actually relatively easy to steal. The animations for Lucent Beam and Eclipse are also very different, so you can tell what she is about to cast and be ready to steal it. Though you should be careful to not be in the range of the beams as you could quickly die.
Vision advantages are key to stealing Eclipse: it turns day into night for 10 seconds so you may lose sight of Luna.
Becomes even better with the Aghanim's Scepter and does a ridiculous amount of damage.
High priority to keep for another fight if you can afford to wait for the cooldown.
Be warned that there is no way of telling the difference between an Eclipse cast by you or Luna, but there is a small moon beam which shines over who cast it. Warn your teammates, especially if you have the Aghanim’s Scepter and are using them as a vessel, as they will often panic and run instead.
If targeted on the ground, it provides 600 AoE ground vision, so can be used to see up cliffs, into the fountain, etc.
If you die while Eclipse is going on, when cast on either you or the ground, it will end. If cast on an allied unit, it will end if the unit dies. Fun Fact, can be cast on allied couriers too!

Medusa

Split Shot

No Longer Stealable.

Mystic Snake

A high damaging nuke that partially refunds its mana cost if units with mana are hit.
Jumps an increasingly large number of times depending on skill level. Damage significantly increases, 35% per jump - at level 4 the final bounce does 550 magic damage. Mana steal does not increase per bounce.
Can be used to farm a creep wave or certain jungle camps which have a lot of mana.
Deals pure damage to targets frozen by Stone Gaze you've previously stolen.

Mana Shield

Toggleable ability that can be stolen whenever Mana Shield is toggled on, but not off.
It offers some damage mitigation, but the mana is generally more useful if used to cast spells rather than to reduce the damage taken.
The effect is instantly lost if the spell is lost or replaced.

Stone Gaze

Large AoE slow that can turn into a long disable if you have a lot of mobility and can stay in front of enemies.
Be warned if your team has a high amount of magic damage: the Petrification caused by Stone Gaze will render the opponents immune to magic damage.
The Stone Gaze buff is not lost if the spell is lost or replaced when activated - great fire-and-forget spell.
Stone Gaze uses the same sound effect of Medusa’s, but you will have large red laser beams shooting out from your eyes, so it can be noticeable. Still, make sure your team doesn't suddenly turn away from Medusa thinking they might get petrified.

Notes

It can be hard to steal what you want from Medusa. Theoretically she should never have Mystic Snake or Stone Gaze stolen since she has two toggle abilities without cast animation at her disposal to prevent it. It is preferable to catch her when she's farming creep waves as she will often use Mystic Snake.

In the middle of a team fight, Medusa often doesn't bother toggling a skill off and on again, so you can steal Stone Gaze. Be warned: the moment you face her you will receive a 35% movement speed slow which can get you killed if you can't blink out or escape fast enough.

Meepo

Earthbind

Long range, but small AoE root.
It is very hard to hit from far away due to the low projectile speed. It is much easier to combo with Telekinesis, though blinking into a group of enemies, and locking down only one of them, can be suicidal.
The short cooldown makes it decent for chasing and ganking enemies.
It provides true sight over units hit by it, so can be useful against invisible heroes.
Fun Fact: the net cast by Earthbind can prevent neutral camps from spawning.

Poof

A nuke which can be used to farm waves decently.
The small AoE can put you in some danger if used in the middle of a team fight.
The 1.5 second cast time is not mitigated by Rubick.
Can Poof to illusions under your control.

Geostrike

Passive Ability. Unstealable.

Divided We Stand

Passive Ability. Unstealable.

Notes

All Meepo clones can be stolen from and each one is considered a different hero, meaning that they have a different spell history. Still, all spells share the same cooldown on Rubick even if you steal them from different clones.

Be extremely careful when stealing from Meepo: he is often much further ahead in farm and levels compared to you. Meepo often has the Blink Dagger and can quickly kill you. Casting Telekinesis on a single Meepo will rarely stop you from dying too.

Mirana

Starstorm

High damaging nuke with a large AoE.
Can be used to farm creep waves, but it doesn’t work as well with neutrals as they have much more HP.
Extremely good in fights and gets better the more mobile you are.
If you have the Aghanim’s Scepter, you will get the passive single Starstorm every 10 seconds too.

Sacred Arrow

Long range and potentially extremely long stun duration.
Great spell to have: enemies will often fail to dodge the arrow as there is no difference with Mirana’s one.
It is also much easier to hit thanks to the total lack of cast animation and is a decent scouting tool.
Good in the early-mid game for farming large neutral creeps or ranged creeps/catapults. Flying arrow will stop neutrals from spawning.

Leap

Pseudo blink escape, whereby you have to be much more careful about the direction you face.
It grants movement and attack speed bonus.
With the 7.07 changes, upon stealing Leap you immediately gain 3 charges. However, if you used all 3 charges on the previous cast, it will go on cooldown until a charge is back, even if you've gotten more charges by stealing the spell again.
Stealing Leap again without another spell in between does not refill charges.

Moonlight Shadow

Large, team-wide invisibility.
Relatively hard to steal as you need to have vision and true sight already in place before she casts something else. You can also steal it if she pops Moonlight Shadow in the middle of the fight and cast Spell Steal while she is still fading.
Good fire-and-forget spell as the buff stays if the spell is lost or replaced. Still, it is good to keep as it allows for your team to gank more effectively.

Monkey King

Boundless Strike

Large AoE stun with a decent duration which does a decent chunk of damage too.
It has a long cast animation on Rubick - the same as the one Monkey King uses. Actually takes longer to affect enemies as a ranged projectile comes out from Rubick, which does the damage, but the enemies are stunned as soon as they are hit by the fissure.

Tree Dance

Either Tree Dance or Primal Spring can be stolen to get both spells.
Tree dance allows for some very quick escapes and enhanced mobility.
Any spells can be cast while on a tree as well as items. If a new spell is stolen while on a tree, you are put onto the ground next to the tree you were on.
Warning: be very careful using Telekinesis while on a tree, the drop from Telekinesis will break trees, and if you break the one you are standing on, you will stun yourself for 4 seconds.

Primal Spring

Either Tree Dance or Primal Spring can be stolen to get both spells.
Primal Spring does a decent amount of damage and provides a good slow.
Good pickoff initiator and can be quickly comboed with Telekinesis.

Jingu Mastery

Passive Ability. Unstealable.

Mischief

Mischief cannot be stolen.
Fun Fact: can be used to walk under the enemy tower range without being attacked by tower or creeps.

Wukong’s Command

Reasonable ultimate to steal, generally quite easy to get as it is the last spell Monkey King casts.
The bonus damage applies to you, and all your soldiers are ranged instead of melee.
Still has the long windup cast animation.
Spell cannot be stolen while Monkey King is channelling Wukong's Command, but you must wait for the spell to start.
Be sure to not stray out of the circle as the spell immediately ends if you do. Hardest part of using this properly is trying to survive.

Morphling

Waveform

High damage nuke and good AoE which also serves as an escape tool.
Useful for farming waves as it does much more damage than Fade Bolt.
Also works as an initiation tool if you don’t have the Blink Dagger yet.
Often easy to steal since Morphling does not cast anything else to farm, but in the late stages of the game often the only thing they cast outside of a fight is Replicate.

Adaptive Strike (Agility)

Now that the Adaptive Strikes are split into two spells, you must be aware of which one you are stealing. Since you have a pitifully low agility normally, the Adaptive strike never does substantial amounts of damage.

Adaptive Strike (Strength)

Slightly reduced maximum stun time and much large push back. Can no longer be used to chain stun people. Still a good spell provided you've morphed all your attributes to strength

Attribute Shift (Agility or Strength gain)

Both are stolen. Toggle off does not count as a cast. Toggling to the other attribute does though.
Stat changes are permanent until the next time you can steal it, and it is advisable to move all available attributes to Strength.
It is cast occasionally in lane, but later on the only way to get it is to force Morphling to run away and change attribute to survive - also, he must not have a replicate up.

Morph

Cannot be stolen.
When Morphling comes out of Morph, you cannot steal anything from him until he casts a new spell. Spells cast before Morph are not carried over.

Naga Siren

Mirror Image

Creates illusions of self, which are largely not useful.
It also disjoins currently flying projectiles, so can be used to dodge spells or attacks.
Illusions currently summoned by Mirror Image will not disappear instantly if the spell is lost or replaced.

Ensnare

Long single target disable, goes through BKB.
Useful to get even if is mitigated by Manta Style and BKB.
Good for pickoffs and can be convenient in team fights as you can simply isolate and render an enemy useless by keeping them away from the battle.
Can be hard to get from Naga Siren as she will rarely use Ensnare unless to chase someone down.

Riptide

Large AoE nuke which also applies a minus armour debuff. Decent damage too.
Good for farming waves and can help in Roshan attempts.
Illusions from either Manta, runes, or a stolen Mirror Image will also cast Riptide around them.

Song of the Siren

Giant AoE disable, but prevents any sort of interaction between your team, units, or buildings.
Primarily used to reset a fight not going your way, or as a last chance teleport canceller.
Be warned that incorrectly used Song of the Sirens can be detrimental to your team too as they can disrupt combos and let your enemies regain cooldowns.
Song of the Siren End does not count as a cast and cannot be stolen.
Stealing a new spell while currently singing does not end the song, but you will lose the ability to end it prematurely. Be careful as you cannot steal from units affected by Song of the Siren, so you must steal from someone outside of the range.
Stealing the song is also hard unless you have a BKB, and you generally need either that or the Aghanim’s so that the range of Spell Steal is big enough to not get caught by the AoE.
If you have the Aghanim’s Scepter and Naga Siren does not, and you both cast Song of the Siren, by casting it out of range and blinking into one another's Song, the Aghanim’s upgraded Song of the Siren overrides the other one.
If neither have the Aghanim’s, then upon blinking in both Rubick and Naga will fall asleep, though both will continue singing.

Notes

Be careful stealing from Naga Siren, especially if she went Radiance as it can screw up your escape plan if you aren't careful. Ensure you know you're stealing from the real Naga Siren too, because otherwise you will waste the cooldown of Spell Steal.

Nyx Asssassin

Impale

Large AoE Stun, but with a much easier aiming time as you have no cast animation.
Best to steal from Nyx when he's farming as it is the only skill he uses to farm.
Great spell to use over and over again, and Nyx Assassin's arsenal of spells is good enough that you could replace Impale for other spells and steal from Nyx again later.

Mana Burn

Single target Nuke that does damage based on the target's Intelligence value, therefore its usefulness depends on the enemy lineup. Also burns the target's mana for the same value.
Although the damage comes before the mana burn, it only deals as much damage as the mana burnt, meaning if your target only has 10 mana remaining, Mana Burn will only deal 10 damage at the most.
Great against high intelligence heroes, especially those with lower HP values like Pugna, Invoker, and Outworld Devourer.
It is also useful against heroes who depend heavily on mana and have a small mana pool, to stop them from casting as many spells. But, those heroes generally increase their mana with flat increases like Arcane Boots as opposed to intelligence items. Also does very little damage to them.
Low cooldown and mana cost so Nyx Assassin is often spamming it in team fights - it is an easy steal.

Spiked Carapace

Defensive Tool which reflects an instance of damage from enemy controlled units, stunning them in the process.
Blocks damage even if the source of damage was magic immune, but it will not reflect or stun them.
Damage from Spiked Carapace cannot be reflected again.
Generally, a spell that is hard to get. Nyx Assassin will pop Spiked Carapace at some point in a fight, usually after running in. But, now it is harder to steal because you can cast it while under Vendetta.

Burrow

Ability given by the Aghanim’s Scepter upgrade. It does not require you to have one to steal it.
While Burrow helps Nyx Assassin by increasing the cast range of various spells, it is specific to Impale and Mana Burn, and therefore does not work with your spells.
If Burrow is lost or replaced while burrowed, you will instantly unburrow.
Your burrow has no digging animation though, so it can be used to hide quickly.
You do get the increased regeneration and the damage mitigation though the latter will rarely help you if you are spotted.
It is important to remember that you can use any item other than Blink Dagger while burrowed, so you can teleport away without revealing yourself or Force Staff teammates to help them get out of trouble.
You can cast any spell if in range, but be careful when casting Fade Bolt as it gives away where you are currently standing.
Easy to steal if you have detection down in place already though Nyx Assassin will generally only sit in places he knows are safe.
Unburrow when cast by Nyx is treated as Burrow, and will grant Burrow if stolen.

Vendetta

Invisible ganking tool which increases movement speed slightly.
Your ranged attack out of invisibility does get the full bonus damage.
Easiest to steal by having sentry wards down and spotting Nyx Assassin run by invisible. The ability to cast Spiked Carapace while under Vendetta makes it harder now.
Be careful to not throw away a possible kill by stealing Vendetta from Nyx Assassin and scaring him away while you could have just blink chain-stunned him with the team.
If you are alone when you spot him, stealing the spell is an easy way to get to safety.

Notes

Stealing from Nyx Assassin is very different depending on the game state. If you are ahead, Nyx Assassin will very rarely roam around for ganks while under Vendetta, and if he is, it is likely he has back up to ensure a kill. If you are behind or even, it is much more likely to spot a solo roaming Nyx Assassin.

It also becomes very different if Nyx Assassin picks up the Aghanim’s Scepter, as his play style generally changes to a more static one, and the rate at which he uses Impale and Mana Burn greatly increases. Stealing in this state also relies on detection as if you wait until he unburrows you will only ever get Burrow.

Pangolier

Swashbuckle

Mobility skill with a small amount of damage.
You get the full vector targeting, so make sure you're used to using it to its full extent.
You don't get Heartpiercer, so the damage is usually minimal, though it will use your orbs if you happen to own any.
Like Pangolier's Swashbuckle, you can immediately cancel a channeled Rolling Thunder by stealing and using Swashbuckle.

Shield Crash

High damage AoE nuke, can be used to farm waves, but the AoE is centered on you. This can put you in danger, and the damage reduction granted by the skill isn't enough to save you in most scenarios.
Can be used to jump up and down cliffs if used at the very edge of one.
Acts in the same way as Pangolier's Shield Crash does if you are currently channeling Rolling Thunder, but unfortunately you don't get the extremely short cooldown.

Heartpiercer

Passive Ability. Unstealable.

Rolling Thunder

A great skill to get. Because the windup is actually part of the cast animation, Rubick doesn't even have it, basically having an instant BKB which also stuns anyone next to you.
You do have to wait for Pangolier to start moving before being able to steal it.
Can be comboed extremely well if the enemy is standing near to a choke point: Telekinesis an enemy right in the centre of the choke, and position yourself so that you constantly bounce back and forth, perma-stunning them. Note that enemies can only be stunned by Rolling Thunder once they're out of the previous stun. Because of this however, you can pull the same tricks as Pangolier: with an Eul's Scepter, if you immediately self-cast the cyclone upon contact with an enemy, they will still be in your Rolling Thunder hitbox when the stun ends, stunning them again immediately.
You can also blink while rolling, which always continues your current trajectory, meaning you can do this combo: Rolling Thunder into the enemy, immediately self-Eul's, once you roll past them blink to before them and stun them again.

Phantom Assassin

Stifling Dagger

A spammable skill which can be used to farm neutrals and creep waves reasonably well.
The dagger now inflicts a percentage of your total attack damage, so on Rubick it does much less damage than before.
Relatively easy spell to steal as Phantom Assassin is often spamming it during fights.
The movement speed slow makes the spell useful for chasing, and the dagger also gives 450 flying vision for 3.3 seconds.
Fun Fact: the dagger does prevent neutral camps from spawning.

Phantom Strike

Medium range blink which needs to be targeted on an allied or enemy unit. It grants a bonus attack speed if you blink on an enemy

Blur

Passive Ability. Unstealable.

Coup de Grace

Passive Ability. Unstealable.

Notes

Phantom Assassin is very dangerous, and if you step within 1000 range, you will immediately be blinked on and die. Even if you have teammates behind you, Phantom Assassin can often assassinate you and get away easily. Be ready to disjoint any currently flying Daggers too.

Phantom Lancer

Spirit Lance

Medium range nuke with that slows the target. It also spawns an illusion that gives vision.
Mediocre without the Aghanim’s Scepter - it is just an extra nuke which can be used in a fight.
The Illusion has potential for juking, but you need to throw the Spirit Lance onto something out of vision and micro it.
With the Aghanim’s Scepter the spell becomes fantastic for farming creep waves and stopping pushes.
Ganking Tip: when trying to kill Phantom Lancer, if he throws Spirit Lance while farming, only the real Phantom Lancer turns to face his target. If the illusions are moving or attacking, they will continue to do so, and won’t turn to face the target.

Doppelganger

Short range escape tool that can be used to go up and down cliffs. If you fail jumping a cliff, pretend that one of the illusions is the real hero and micro it - leave your hero alone and hopefully the opponents will believe he is just an illusion.
Can also be used to disjoint projectiles, and also makes you invulnerable so you won't be affected by spells like Glimpse.
Upon landing, two additional illusions are created: one is a normal illusion, while the other one does no damage and takes normal damage. If you can, you should micro the latter - it looks brighter than the former.

Phantom Rush

Since 7.07 gave Phantom Rush a toggle, you can now actually steal Phantom Rush. While Phantom Lancer's illusions gain the ability, yours do not as illusions do not get any stolen spell.
You don’t charge in melee range, but up to your attack range. You get the agility bonus, but as an INT hero you inflict no additional damage.

Juxtapose

Passive Ability. Unstealable.

Notes

When stealing from Phantom Lancer, do not stay too close to farming illusions. If Phantom Rush activates on any of them when he right clicks you, your Blink Dagger will be cancelled. If you get purged by the real Phantom Lancer, you are dead.

Also make sure you steal from the real Phantom Lancer as otherwise is a wasted Spell Steal cooldown. Spell Stealing anything meaningful from Phantom Lancer is now very hard as he can toggle Phantom Rush on and off at will.

Razor

Plasma Field

Decent nuke, but requires some aiming. It hits for the maximum damage when the unit is standing at 700-900 range away.
Also provides flying vision, so it is great for a Roshan fight.

Static Link

A damage stealing debuff which requires you to remain close to the target - it can get you in trouble if there are more enemies close by.
It provides shared vision, meaning you get to see whatever the linked target sees, which can be useful if you Static Link someone like Night Stalker (death wish) or Keeper of the Light.
Good when combined with Telekinesis for some guaranteed damage steal.
The spell can be lost or replaced without instantly breaking the Static Linking, making it a good fire-and-forget spell if you aren't in too much danger at the time.

Unstable Current

Passive Ability. Unstealable.

Eye of the Storm

Single target damaging DoT which hits the unit with the lowest current HP value, but once again requires you to be in close range.
Does not work on Roshan.
Does not work on buildings unless you have the Aghanim’s Scepter, in which case it won’t lower the building's armour. Only really useful if the enemy team isn't alive and you can freely hit the base.

Riki

Smoke Screen

Large AoE silence which also adds a slight movement speed slow and a large miss chance.
Extremely good at disrupting team fights. Works well with Telekinesis as you can throw enemies back into the smoke.
Small cast range mean you may be in danger if you're out of position.
There is no way of telling whether a Smoke Screen is cast by you or Riki, so make sure your teammates know which one is yours.

Blink Strike

Short cooldown and medium range blink which needs to target a unit.
Acts as a weak nuke that can finish off targets.
Good chasing tool, can also be used as a small range increaser for initiations.

Cloak and Dagger

Passive Ability. Unstealable.

Tricks of the Trade

Difficult spell to steal as Riki will often have his other spells off cooldown the moment Tricks of the Trade ends.
Most useful as a hiding tool to dodge projectiles, made easier as you have no cast animation.
Damage is pretty small. It hits units in the fog, but not invisible ones, so can finish fleeing enemies.
With the Aghanim’s Scepter the duration increases, and it can be used to escape into an ally if you need to run. If the ally dies, Tricks of the Trade will continue stationary where they died.
You cannot cast other spells while under the effect of Tricks of the Trade.

Notes

Stealing from Riki is difficult without detection already down, and if the Riki is farmed you could be killed quickly if you step within range of Blink Strike. Be sure to have a Force Staff so that you can get out of Smoke Screen to disable him and get away.

Shadow Fiend

Shadowraze (near, medium, and far)

The Darker the face, the smaller the range.
Good damaging nuke which affects a reasonable area.
You only steal the specific Shadowraze cast, not all 3. Knowing which Shadowraze you have is important if you need to use it to finish an enemy.
The Far raze is the best, as it keeps you the furthest away from danger, and is the more versatile in terms of effective AoE as you can hit a wide range of targets.
The Near raze is the most dangerous, but it is the easiest to aim as you can simply blink in, Telekinesis, and Shadowraze.
Very good to fire-and-forget as you can easily obtain another Shadowraze if needed.
The stacking damage amplifier is useless for Rubick as you will rarely get access to multiple razes in quick succession.

Necromastery

Passive Ability. Unstealable.

Presence of the Dark Lord

Passive Ability. Unstealable.

Requiem of Souls

Large AoE ultimate that does a huge amount of damage if done correctly. It takes the number of souls which Shadow Fiend currently has when you steal the spell, and if he has the Aghanim’s Scepter you get the extra souls regardless if you have the item or not.
If you have the Aghanim’s, the only extra bonus you get is the returning Requiem and the heal. You used to get the free Requiem of Souls cast upon your death, but it was removed around 6.88-89.
As Rubick you can easily pull off a full Requiem combo on an enemy. If you have the Blink Dagger, you can blink directly next to the enemy, Telekinesis them, don't move them, and walk a few steps to get directly under them. Start channelling Requiem as quickly as possible as if they hit the ground before you finish, you will displace each other. Alternatively, if you are already in close, you can Telekinesis a target, Blink directly under them, and start channelling.

Slark

Dark Pact

Decent damaging nuke, obviously with downsides because of self damage (150 damage to yourself at level 4). You do not possess the high HP regen of Slark, making it not as viable as a long term farming tool.
Decent to farm neutrals with if you find yourself about to go back to base because of lack of mana, but high on HP.
Very easy to steal as Slark commonly uses Dark Pact to farm. The spell can be stolen off of the initial cast of Dark Pact - the damage instances do not need to start occurring to steal it.

Pounce

Medium range movement spell which requires you to face the correct direction. Can be used to go over cliffs.
Does not do much damage.
It is dangerous to use in fights as puts you right next to the danger, especially since there is a Slark in the game.
Decent pickoff tool as it can prevent enemies from escaping and is easy to combo with Telekinesis. Be warned that your escaping Pounce can be stopped by an enemy hero standing in front of you. You cannot Pounce out of the leash caused by Pounce.

Essence Shift

Passive Ability. Unstealable.

Shadow Dance

Useful spell to steal that provides you with passive regeneration and a very reliable escape tool.
You get the bonus movement speed, which helps to detect whether the enemy can see you.
Difficult to steal as you cannot steal from Slark when he is under the effect of Shadow Dance, and he will very often cast Dark Pact and Pounce during that time.
Passive HP regeneration also allows you to kill neutrals at no HP cost.

Notes

Stealing from Slark is a hard task due to the hero's skill set and normal item builds. Often he will just jump on you, and you can do very little to defend yourself. If Slark is played correctly, you will die as soon as Dark pact ends, without giving you any time to disable him.

Make sure you get significantly more defensive items, like Glimmer Cape, Eul's Scepter of Divinity, and Ghost Scepter. Already placed detection gives you the initiation on him which can get you a spell, though his skill set doesn't work well with your own and is difficult to utilise effectively individually.

Sniper

Shrapnel

Large AoE DoT and slow which lasts quite a while - very useful in fights and even for farming. Comes with 3 charges whenever stolen, regardless of how many were used before.
It is affected by the “Charges Bug”: using all charges will put the spell on cooldown, replacing the spell and restealing it will give you all 3 charges back, but the game doesn’t check for the number of charges so the spell remains on cooldown.
Easy to steal as sniper will often use it to get the vision of towers or neutrals in the Fog of War.
Has an extremely large cast range, so can be used very safely.
If you have the Aghanim’s Scepter and are rapidly changing spells, it may be wise to spam 2 charges and replace the spell, so that it may be stolen again for more free charges.
Be warned, there is no way to tell the difference between a Shrapnel cast by you or by Sniper, and you should make sure that your team knows you have it.

Headshot

Passive Ability. Unstealable.

Take Aim

Passive Ability. Unstealable.

Assassinate

Huge ranged single target nuke.
At high levels does a lot of damage and has a relatively short cooldown, so can be used to chip down enemies easily. The 2-second charge time is not mitigated, though you will get vision and true sight of the target while charging.
Applies a mini-stun to the target when the projectile hits, so can cancel teleports and channelling spells, and goes through magic immunity.
If the target walks outside the cast range (usually accomplished by teleporting or by blinking) the charging stops.
The Aghanim’s Scepter turns the cast into an AoE, but changes the damage from a set magic damage nuke into a physical damage attack based on your attack damage. Not great on Rubick as it deals only 229 damage at level 11 with the level 3 ultimate. It also adds a guaranteed Headshot proc, slowing the enemies after the mini stun.
If you have the Aghanim’s Scepter and Sniper doesn’t, the Assassinate you steal will have no channelling windup and will instantly fire at enemies, and still cancels teleports and debuffs them with a Headshot. If the damage really matters to you, you can drop the Aghanim's Scepter right before you cast Assassinate, turning your cast into a single target again, but still retaining the instant cast. Probably a bug.

Notes

Because of Sniper's huge attack range, it would be wise to watch your step if you plan to steal from him. He can slow and cancel your Blink Dagger from a long distance, which could lead to your death. Be very careful of walking into active Shrapnel casts.

Spectre

Spectral Dagger

Huge range nuke with a decent damage which also slows the target.
It leaves a Spectral trail behind the target as they walk, which gives you free pathing when followed. Can be great for chasing enemies as well as for an escape. Superb for ganking attempts as the enemy can rarely get away because the Dagger gives vision of the target.
Can be used to farm decently though its damage isn't particularly high.
The Spectral Dagger cannot be disjointed, and if the target blinks away it will still follow them.
Can also be ground targeted.
Any unit it hits on the way, no matter how far from the initial location, will be damaged and leave their own trail.
If the Spectral Dagger hits an invisible unit, the hero's silhouette is revealed, though it cannot be interacted with at all unless you have true sight.

Desolate

Passive Ability. Unstealable.

Dispersion

Passive Ability. Unstealable.

Reality

Sub-ability granted by Haunt, used to jump to an illusion created by Haunt.
Both Haunt and Reality can be stolen from Spectre to get Haunt.
It costs no mana so it can be used during a fight to rapidly get around and assist your team. Be careful as the illusions created by your Haunt are very easy to kill.

Haunt

Large ultimate that gives vision of the entire enemy team and cancels their Blink Daggers.
The long cooldown makes it a decent fire-and-forget spell, though its impact overall is low.

Templar Assassin

Refraction

Buff which gives you several bonus damage attacks and also blocks the next few damage instances you receive.
Can be very useful when tower diving or while being under tower to deceive the enemies about your effective HP.
Damage block is especially useful if you have the Blink Dagger - if you do not take any damage due to Refraction, it will not put your Blink Dagger on cooldown.

Meld

Invisibility spell which does not allow you to move.
Attacking out of Meld gives an attack bonus damage and applies a minus armour debuff on the target.
Useful when doing Roshan, and can even be used to hide in places and around corners when running from enemies.
The spell has an instant fade time, so in order to replace it while still using it, you need to first cast Spell Steal, and Meld while the projectile is in the air.
Meld has no time limit and will last until you move or cast something.

Psi-Blades

Passive Ability. Unstealable.

Psionic Trap

Great scouting tools which can be placed anywhere, especially important in the Roshan Pit as it can show you exactly when it is about to die.
Traps placed by you do not disappear when the spell is lost, but you lose the ability to detonate the nearest one. They can still be detonated individually.
The traps do not block neutral spawns, so they can useful if placed in a camp to keep track of whether or not enemies are farming them.

Notes

Templar Assassin is very dangerous: she can kill you instantly for most of the game, and she almost always has the Blink Dagger. Also, you cannot cancel her Blink Dagger with Fade Bolt if she has Refraction active.

Be very careful when stealing from TA. Be sure there is detection down already so that you know there aren't Psionic Traps that can hinder your escape. If she Blinks on you, it also allows you to interrupt her Meld attack and Telekinesis her out of it.

Terrorblade

Reflection

Large AoE slow which can do a lot of damage to the opposing team if they are heavily based on auto-attacks.
900 AoE means that you do have to be close by when casting, which can put you in danger.

Conjure Image

Despite the skill description saying that it creates an illusion of Terrorblade, it just creates an illusion of your hero.
Illusions don't do much damage, but they can be quite useful scouting tools.
All illusions currently summoned do not disappear if the spell is lost or replaced.
Illusions are transformed by Metamorphosis.

Metamorphosis

Transformation ability.
Adds a reasonable amount of damage to your auto attacks, but at the cost of some movement speed. Rubick does not gain the additional attack range normally granted.
Metamorphosis does not end instantly if the spell is lost or replaced. Due to the long cooldown, it is advisable to use it and steal something else.

Sunder

Short to medium cast range spell which swaps HP pools with a target.
Can target both allied and enemy heroes, and even illusions.
You will rarely get Sunder, so often the enemies will be surprised, and you could score a kill out of it.

Troll Warlord

Berserker’s Rage

Toggling to range or melee are both counted as casting Berserker's Rage and will grant it when stolen.
Activating it will cause your attacks to become melee, gives you the chance to bash, and some additional armour.
You are reverted into range form when the spell is lost or replaced.
Not useful at all, but you will usually steal it if Troll Warlord is trying to block you from stealing good spells as he can just toggle it.

Whirling Axes (Ranged)

Only the last used type of Whirling Axes is stolen at one time as they are different spells with separate cooldowns.
Requires a target to throw axes towards. Long range slow which lasts for a decent time, but does very little damage. Can be useful when ganked or when going for pickoffs to disable the target.

Whirling Axes (Melee)

Only the last used type of Whirling Axes is stolen at one time as they are different spells with separate cooldowns.
It is not targeted and will immediately trigger, throwing axes outwards in a spiral.
Does a decent amount of damage, and debuffs enemies with a 60% miss chance which can save your life in gank attempts.
The damage is decent so it can be used also for farming waves and neutrals as you take much less damage from the camps.

Fervor

Passive Ability. Unstealable.

Battle Trance

Global ranged, huge attack speed steroid.
Effectiveness depends on your team composition, but it is generally extremely useful.
If the enemy team is dead or caught off guard, you can very quickly destroy structures.
Highly spammable and may be worth keeping for a while to push towers down.
Losing or replacing Battle Trance does not instantly remove the buff so it can be a good fire-and-forget spell during a team fight.

Ursa

Earthshock

Small AoE nuke which also slows.
Quite dangerous to use in team fights, but if you have many movement speed or mobility items, the 55% movement speed slow is enough to escape.
Does a decent amount of damage when maxed and costs a minimal amount of mana, so it can be used to farm creep waves quite fast.
Relatively easy to steal as Ursa often uses it to farm creep waves.

Overpower

Self-buff which greatly increases your attack speed for a few attacks.
Not particularly useful, though can be used to farm neutrals, and adds a little pushing power if you are given a lot of room.
The buff does not instantly disappear if Overpower is lost or replaced.

Fury Swipes

Passive Ability. Unstealable.

Enrage

Large amount of incoming damage mitigation when cast, which can save you in a team fight very easily.
Be warned that if you do not have the Aghanim’s Scepter, you could die in a single stun, so don't depend on Enrage too much. With the item you can pretty much guarantee to bait out a disable from the enemy team, but beware of silences and hexes as you cannot cast it when affected by them
Only often used by Ursa in a fight or when taking Roshan, so can be rather hard to steal.

Notes

Stealing from Ursa is very dangerous because he has a built in slow and the Blink Dagger. Abyssal Blade is often purchased, meaning that if you are ever in attack range, you are basically dead. It is preferable waiting for him to use Earthshock before going in so that you can get out.

If the Ursa has the Aghanim’s Scepter, you shouldn't even attempt to steal from him as he will blink on you and instantly remove your Telekinesis when cast.

Vengeful Spirit

Magic Missile

Medium range stun which can easily be stolen due to Vengeful Spirit's long cast animation. Can be disjointed.

Wave of Terror

Long range, low damaging nuke that makes up for it by lowering armour.
Gives vision so can be used to scout ahead or into Roshan.
Good for farming creep waves as it greatly increase your auto attack damage.
It boosts the damage of allied carries when fighting, attacking the Roshan, or in team fight.

Vengeance Aura

Passive Ability. Unstealable.

Nether Swap

Spell with a huge impact that can save teammates.
Have your Blink Dagger ready when you cast it so you can get back to safety too.
Vengeful Spirit is often under levelled as a support, and the spell really isn't great at level 1.
With the Aghanim’s it becomes interesting to use because of its short cooldown and ability to swap creeps. Most importantly, when you have the Aghanim’s and have stolen Nether Swap, upon dying you will produce an illusion until you respawn. It can cast all your spells, including Spell Steal and any spell your illusion can steal. All your main spells come off cooldown when the illusion is created.

Notes

When stealing spells from Vengeful Spirit, try to not get your Blink Dagger cancelled by a long range Wave of Terror. Be ready to blink out straight away if you are swapped into the enemy team.

Venomancer

Venomous Gale

Long range AoE slow which does a decent amount of damage.
Great for pickoffs and can be very disruptive in team fights.
Can also be used to farm waves although the DoT makes it harder to last hit sometimes.

Poison Sting

Passive Ability. Unstealable.
You do get Poison Sting when you steal Plague ward. It works on both your own regular attacks and the wards themselves, but you get no skill icon.

Plague Ward

Summonable wards which can attack things.
Great for scouting up high grounds or over trees. Useful to ensure the area you're in is safe and to deward without risking anyone's life.
Can be spammed to defend towers.
Also very good for farming the jungle since the damage type was changed.

Poison Nova

Huge AoE DoT that does an absurd amount of damage. It costs a lot of mana, so watch your mana pool if you want to cast it.
Difficult to utilise properly without a few mobility items.
With the Aghanim’s Scepter it inflicts even more damage.
Relatively easy to steal unless Venomancer has the Blink Dagger.

Viper

Poison Attack

Autocast (Orb) ability. Unstealable.

Nethertoxin

With 7.07, Nethertoxin is now an active ability. It ejects a pool of AoE DoT which reduces magic resistance of any enemy standing in it and breaks passives.
Magic resistance reduction stacks with Null Field, greatly increasing the magic damage of the team.
Very good against Viper himself as it also breaks his passive which grants magic resistance.

Corrosive Skin

Passive Ability. Unstealable.

Viper Strike

Used to be very simple to steal as it was the only spell Viper had available.
Be careful to not cast Fade Bolt and not auto attack Viper while stealing as Corrosive Skin will damage you and cancel your Blink Dagger.
Single target BKB-piercing DoT and huge movement and attack speed slow. Very good to throw onto a carry and then change spell. Perfect fire-and-forget spell as is a near guaranteed steal.
It becomes even better with the Aghanim’s as it lowers the mana cost and almost doubles the cast range. Without it, the cast range is kinda low (500) and it can get you in trouble.

Weaver

The Swarm

Large AoE DoT which gives vision over anyone hit by it.
The minus armour amplifies the team's damage.
It has a significant cooldown, and all of Weaver's spells are decent, so it is a good fire-and-forget spell.

Shukuchi

Incredible spell which acts as both a farming and a mobility tool.
The maximum movement speed along with the invisibility makes you much harder to kill. Often worth keeping to use it over and over.
Because it is often used to farm, can be quite easy to steal.

Geminate Attack

Passive Ability. Unstealable.

Time Lapse

Reverts the last 5 seconds of damage and mana usage.
Not easy to get as upon cast usually greatly relocates Weaver.
Does not revert cooldowns, so be mindful of Time Lapsing into 5 enemies and not having Spell Steal or Telekinesis up. Also applies a strong dispel upon cast, which is less useful without the Aghanim’s.
With the Aghanim’s Scepter, it turns Time Lapse into an incredible saving tool for your allies, and it costs no mana. Incredible for getting 5 seconds worth of chip damage on a tower.
The buyback Time Lapse trick cannot be done by Rubick as the spell is lost on death.

Notes

Stealing from Weaver can be tricky as he will often use both The Swarm and Shukuchi to farm. The Swarm is used to busy creep waves while he attacks them, and Shukuchi between waves and for finishing off partially damaged creeps.

Be careful of getting jumped by Weaver: if he hits you with The Swarm and catch up to you with Shukuchi, you could easily die. Be certain about the last spell Weaver cast because if you blink in thinking to steal Shukuchi, and end up with The Swarm, he could just kill you.

Weaver also often gets the Linken's Sphere, meaning that spell stealing is quite hard as it requires you to be in the range of Fade Bolt or Telekinesis. A possible combination: Blink in, Fade bolt to break the Linken's Sphere, Telekinesis to lock him down, Spell steal to get Shukuchi, and finally Shukuchi away to safety.

Header image and all hero pictures: Valve