Amber Prison [Classic Sixth Edition] Nightmare Snake you may remove a hit

you may remove a hit counter from a card that player owns in exile

Set: Double Masters 2022 Type: Creature — Wall Rarity: Uncommon Cost: {1}{W} Defender

Set: Homelands Type: Instant Rarity: Rare Cost: {U} You may tap or untap target creature

sleeper agent

Each copy targets a different one of those creatures

Amber Prison [Classic Sixth Edition] Nightmare Snake you may remove a hitSet: Classic Sixth Edition Type: Artifact Rarity: Rare Cost: {4} You may choose not to untap Amber Prison during your untap step. {4}, {T}: Tap target artifact, creature, or land. That permanent doesn't untap during its controller's untap step for as long as Amber Prison remains tapped.