Ultra Necrozma (164)

AbilitiesUltra Burst: This Pokémon can't attack unless your opponent has 2 or fewer Prize cards remaining.Attacks{Psychic}{Metal}Luster of Downfall: Discard an Energy from your opponent's Active Pokémon. Damage: 170

Ultra Necrozma - Sun & Moon: Cosmic Eclipse - Pokemon

Ultra Necrozma Cosmic Eclipse 164/236 Values - MAVIN

Pokemon Sun & Moon Ultra Prism Card: Dialga GX 164/156 Rainbow Ultra R - Recaptured LTD

Ultra Necrozma Cosmic Eclipse, Pokémon

Pokemon TCG Sun & Moon: Ultra Prism - Dusk Mane Necrozma Elite Trainer — MyShopville

Ultra Necrozma - Sun & Moon: Cosmic Eclipse - Pokemon

Ultra Burst - Bulbapedia, the community-driven Pokémon encyclopedia

Ultra Necrozma Expanded Deck Profile and Battles PTCGO

How was this card able to damage my Pokemon 170 each turn when I had 6 prize cards? Is it a big or did I miss something? : r/ptcgo