Martial Impetus is a common Enchantment — Aura card from Commander Legends: Battle for Baldur's Gate (CLB), collector number 33. Current market price: $0.29 (foil $0.29), TCGplayer market prices via Scryfall.
Enchant creature Enchanted creature gets +1/+1 and is goaded. (It attacks each combat if able and attacks a player other than you if able.) Whenever enchanted creature attacks, each other creature that's attacking one of your opponents gets +1/+1 until end of turn.
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