A parasite Pokémon with the ability to take control of other creatures it considers strong enough for its own survival. It will not leave the host body until it is dead.

Once during your turn, if this Pokémon is in the Active Spot, you may choose a Pokémon from your opponent's discard pile and and put it onto this Pokémon as a Lvl.X card. If you do, this Pokémon gets +30 HP, and ignore all Energy in the costs of attacks used by this Pokémon. Any attached cards, damage counters, Special Conditions, turns in play, and any other effects remain on the new Pokémon. You can’t use more than 1 Symbiote Ability in a game.

Ditto X

Ability: Symbiote