Kill! Destroy! is a uncommon Instant card from Unhinged (UNH), collector number 58. Current market price: $1.36 (foil $11.11), TCGplayer market prices via Scryfall.
Destroy target nonblack creature. Gotcha — If an opponent says "kill" or "destroy," you may say "Gotcha!" When you do, return Kill! Destroy! from your graveyard to your hand.