In the Eye of Chaos [Legends] Nightmare Fish Beast its marines must rely on

its marines must rely on more cautious strategies

The ATK of the selected monster becomes 0

except for the Xyz Summon of an Insect-Type monster

Set: Shadows over Innistrad Type: Instant Rarity: Uncommon Cost: {3}{W} Creatures you control get +1/+1 and gain lifelink until end of turn

Set: Duels of the Planeswalkers Type: Instant Rarity: Common Cost: {1}{G} Destroy target artifact or enchantment

In the Eye of Chaos [Legends] Nightmare Fish Beast its marines must rely onSet: Legends Type: World Enchantment Rarity: Rare Cost: {2}{U} Whenever a player casts an instant spell, counter it unless that player pays {X}, where X is its mana value.