Emberheart Challenger

Creature — Mouse Warrior{1}{R}2/2

Haste Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) Valiant — Whenever this creature becomes the target of a spell or ability you control for the first time each turn, exile the top card of your library. Until end of turn, you may play that card.

Colour identity Red · Prowess, Valiant, Haste

In short

Emberheart Challenger has 5 listed printings; the most valuable is the Secret Lair printing from SLP at US$16.19 on TCGplayer's market price. Prices below are the cheapest in-stock listing in the United States.