pokemon Crown Zenith: Galarian Gallery Giratina VSTAR (Secret)

VSTAR Power
Ability — Star Requiem
You can use this attack only if you have 10 or more cards in the Lost Zone. Your opponent's Active Pokémon is Knocked Out. (You can't use more than 1 VSTAR Power in a game.)

VSTAR rule — When your Pokémon VSTAR is Knocked Out, your opponent takes 2 Prize cards.