Anzrag, the Quake-Mole is a mythic Legendary Creature — Mole God card from Murders at Karlov Manor (MKM), collector number 356. Current market price: $6.47 (foil $6.85), TCGplayer market prices via Scryfall.
Whenever Anzrag becomes blocked, untap each creature you control. After this phase, there is an additional combat phase. {3}{R}{R}{G}{G}: Anzrag must be blocked each combat this turn if able.