Karlach, Fury of Avernus is a mythic Legendary Creature — Tiefling Barbarian card from Commander Legends: Battle for Baldur's Gate (CLB), collector number 186. Current market price: $19.36 (foil $27.24), TCGplayer market prices via Scryfall.
Whenever you attack, if it's the first combat phase of the turn, untap all attacking creatures. They gain first strike until end of turn. After this phase, there is an additional combat phase. Choose a Background (You can have a Background as a second commander.)
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