Pot of Duality [DUSA-EN084] Ultra Rare Legacy of Darkness You can only use this

You can only use this effect of "Coach King Giantrainer" up to thrice per turn

inflict damage to your opponent equal to half the ATK that monster had on the field

but make its ATK/DEF 0

Halve the ATK and DEF of all monsters on the field

Once per turn: You can banish 1 "Crystal Beast" monster from your GY

Pot of Duality [DUSA-EN084] Ultra Rare Legacy of Darkness You can only use thisSet: Duelist Saga Card type: Normal Spell Rarity: Ultra Rare Excavate the top 3 cards of your Deck, add 1 of them to your hand, also, after that, shuffle the rest back into your Deck. You can only activate 1 "Pot of Duality" per turn. You cannot Special Summon during the turn you activate this card.