Clocknapper is a rare Creature — Human Spy card from Unstable (UST), collector number 29. Current market price: $0.28 (foil $0.40), TCGplayer market prices via Scryfall.
When this creature enters, choose beginning phase, first main phase, combat phase, postcombat main phase, or ending phase. Steal that phase from target player during their next turn. (That phase occurs as though it's your turn instead.)