Gyarados GX (18/111) [Sun & Moon: Crimson Invasion] XY65 but the opponent's monster was

but the opponent's monster was not destroyed by the battle: You can make the opponent's monster's ATK 0 (even after this card leaves the field or the monster becomes unaffected by card effects)

from each player's hand

Set: X Record Pre-Release Promos Card type: Tamer Rarity: Rare Play Cost: 4 [Start of Your Turn] If you have 3 or fewer security cards

you can banish monsters from your hand

Set: Sun & Moon: Base Set Type: Fairy Rarity: Holo Rare Retreat cost: Colorless

Gyarados GX (18/111) [Sun & Moon: Crimson Invasion] XY65 but the opponent's monster wasSet: Sun & Moon: Crimson Invasion Type: Water Rarity: Ultra Rare Retreat cost: Colorless,Colorless,Colorless,Colorless