Yveltal GX

Darkness

Heal from this Pokémon the same amount of damage you did to your opponent’s Active Pokémon.

Colorless · Colorless · Colorless

This attack’s damage isn’t affected by Weakness or Resistance.

Darkness

If your opponent’s Active Pokémon has exactly 4 damage counters on it, that Pokémon is Knocked Out. (You can’t use more than 1 GX attack in a game.)