A Pokémon who uses Substitute loses 25% of their HP to create a Substitute with that amount of HP. The Substitute shares all other stats with whichever Pokémon is behind the Substitute. If the Pokémon using Substitute has less than 25% of its HP remaining, Substitute will fail. The Substitute will take any direct damage and will block non-damaging moves (cause them to fail) until it is broken or the user switches out.
Substitute blocks all forms of stat-reduction mentioned (Acid, Aurora Beam, Bubble, Bubblebeam, Captivate, Charm, Constrict, Cotton Spore, Crunch, Crush Claw, Earth Power, Energy Ball, Fake Tears, Featherdance, Flash, Flash Cannon, Focus Blast, Icy Wind, Iron Tail, Kinesis, Leer, Luster Purge, Memento, Mirror Shot, Mist Ball, Mud Bomb, Mud Shot, Mud-Slap, Muddy Water, Octazooka, Psychic, Rock Smash, Rock Tomb, Sand-Attack, Scary Face, Seed Flare, Shadow Ball, Smokescreen, String Shot, Sweet Scent, Tail Whip and Tickle) on the Substituted Pokémon except for those that are self-inflicted (Close Combat, Draco Meteor, Hammer Arm, Leaf Storm, Overheat, Psycho Boost and Superpower). For the attacks Substitute blocks, those that would normally cause damage still damage the Substitute, however the Substituted Pokémon cannot have its stats lowered if the Substitute is attacked. Any self-inflicted stat-reduction also reduces the stats of the Substitute.
Substitute does not block any form of self-inflicted stat-increase (Acid Armor, Agility, Amnesia, Ancientpower, Barrier, Bulk Up, Calm Mind, Charge, Charge Beam, Cosmic Power, Curse, Defend Order, Defense Curl, Double Team, Dragon Dance, Growth, Harden, Howl, Iron Defense, Meditate, Metal Claw, Meteor Mash, Minimize, Nasty Plot, Ominous Wind, Rock Polish, Sharpen, Silver Wind, Skull Bash, Steel Wing, Stockpile, Swords Dance, Tail Glow and Withdraw). The only exception to this rule is Acupressure. Any self-inflicted stat-increase also increases the stats of the Substitute. Substitute also does not block Focus Energy.
Substitute blocks Acupressure, Ghost’s Curse, Dream Eater, Embargo, Gastro Acid, Leech Seed, Lock-On, Mind Reader, Nightmare, Pain Split, Psycho Shift, Switcheroo, Trick, Worry Seed and Yawn. However, if Yawn is used on a Pokémon who then uses Substitute, the Pokémon will still go to sleep as per normal.
Substitute doesn't block After You, Attract, Boomburst, Bug Buzz, Chatter, Conversion2, Curse, Defog, Destiny Bond, Disable, Disarming Voice, Echoed Voice, Eerie Impluse, Encore, Foresight, Grasswhistle, Growl, Grudge, Guard Swap, Haze, Heal Bell, Heart Swap, Helping Hand, Hyper Voice, Imprison, Me First, Metal Sound, Mimic, Miracle Eye, Odor Sleuth, Perish Song, Power Swap, Psych Up, Reflect Type, Relic Song, Roar, Role Play, Round, Screech, Sing, Sketch, Skill Swap, Snarl, Snatch, Spite, Supersonic, Taunt, Torment, Transform, Uproar and Whirlwind.
Pokémon with Flash Fire, Motor Drive, Soundproof, Volt Absorb and Water Absorb will still activate when targeted by the corresponding type of attack (this includes Thunder Wave and Will-O-Wisp) if they are behind a Substitute.
Present will damage the Substitute if it chooses damage, but will heal the Pokémon behind the Substitute if it chooses heal.
Substitutes can be Baton Passed to another Pokémon. The Substitute will keep its original HP but will gain the types and stats of the new Pokémon. The Substitute does not block damage from Spikes or Stealth Rock; the Pokémon receiving the Substitute still takes damage from them. The Substitute does block poison from Toxic Spikes.
If a multi-hit move (Arm Thrust, Barrage, Bone Rush, Bonemerang, Bullet Seed, Comet Punch, Double Hit, Double Kick, Doubleslap, Fury Attack, Fury Swipes, Icicle Spear, Pin Missile, Rock Blast, Spike Cannon, Triple Kick and Twineedle) breaks the Substitute any successive hits will damage the Pokémon that was behind the Substitute.
Partial-trapping moves (Bind, Clamp, Fire Spin, Magma Storm, Sand Tomb, Whirlpool and Wrap) will do their normal damage to the Substitute, but the end of turn damage is blocked. The Substitute also blocks the trapping effect for 2-5 turns.
If a Pokémon with a Substitute hurts itself in confusion, the damage goes to the Pokemon, not to the Substitute. The same applies for recoil damage from any recoil move (Brave Bird, Double-Edge, Flare Blitz, Head Smash, Struggle, Submission, Take Down, Volt Tackle and Wood Hammer).
Status moves can be reflected back from behind a Substitute with Magic Coat even though they would normally be blocked by the Substitute.
Life Orb’s 10% HP recoil does not activate when attacking a Substitute, but the 30% damage increase does.
All attacks dependent on the remaining HP of the Pokémon (Brine, Crush Grip, Endeavor ,Eruption, Flail, Reversal, Super Fang, Water Spout and Wring Out) have their damage based on the HP of the Pokémon, not of the Substitute.
False Swipe can break Substitutes.
Substitute does not block the secondary effects of Rapid Spin.
Pokémon that Learn this Move via Level-Up
Pokémon that Learn this Move via TM90
Pokémon that Learn this Move via Sketch
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