Thievul (113/189) [Sword & Shield: Darkness Ablaze] Miscellaneous Cards you can use this effect

you can use this effect on 1 monster that has attacked this turn and is equipped with a Union Monster

You may choose to have that player shuffle their hand into their Deck and draw a new hand

When your opponent Normal or Special Summons exactly 1 monster (and no other monsters are Summoned) while this monster is on the field: You can make that monster lose ATK equal to its Level x 200 (until the end of this turn)

Set: Raging Battle Card type: Effect Monster Rarity: Ultra Rare Attack: 2400 Defense: 1000 This card cannot be destroyed by battle with a monster that has the same ATK

Set: XY: Flashfire Type: Grass Rarity: Rare Retreat cost: Colorless

Thievul (113/189) [Sword & Shield: Darkness Ablaze] Miscellaneous Cards you can use this effectSet: Sword & Shield: Darkness Ablaze Type: Darkness Rarity: Rare Retreat cost: Colorless