Tavern Brawler is a common Legendary Enchantment — Background card from Commander Legends: Battle for Baldur's Gate (CLB), collector number 200. Current market price: $0.26 (foil $0.35), TCGplayer market prices via Scryfall.
Commander creatures you own have "At the beginning of your upkeep, exile the top card of your library. This creature gets +X/+0 until end of turn, where X is that card's mana value. You may play that card this turn."
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