Silvally GX (Secret) [SM - Cosmic Eclipse]

[2] Brave Buddies (50+)
If you played a Supporter card from your hand during this turn, this attack does 70 more damage.

[2] Silver Knight GX
If your opponent's Active Pokémon is an Ultra Beast, that Pokémon is Knocked Out. (You can't use more than 1 GX attack in a game.)