When a Pokémon with this Ability is hit by a damage-dealing move (with some exceptions mentioned below), the Pokémon's types will be changed to the type of the move that it was hit by. Even if the Pokémon with Color Change has two types, it will only have a single type after the effect is applied.
Color Change does not activate if the Pokémon is hit by a move of the same type as itself, even if the Pokémon has two or three types (the latter from Forest's Curse or Trick-or-Treat). Color Change does not activate if the Pokémon's substitute is hit.
Status conditions are inflicted before Color Change activates. As a result, even if Color Change would make the Pokémon become a type that is immune to the status condition, the Pokémon can still be afflicted with the status condition; for example, a Pokémon with Color Change that is hit by Poison Sting has a chance to be poisoned before it becomes Poison-type.
Color Change now activates after the last hit of a multistrike move. Future Sight and Doom Desire now activate Color Change when they hit (they do not activate Color Change when used).
When the Pokémon is damaged by a move, its type changes to match the type of that move.* When it's damaged by a move, the Pokémon's type changes to the type of the move that damaged it!*
When it's damaged by a move, the Pokémon changes type to the type of the move that damaged it. The Pokémon will return to its original type when it goes to a different floor.
In animation
Pokémon animated series
Harrison's Kecleon
Angela's Kecleon
Gizmo's Kecleon
The Pokémon turns invisible to match its surroundings.
Kecleon's body turns invisible to blend in with its surroundings. The only thing visible after it changes is the red stripe on the center of its stomach.