Keldon Berserker

The reward clause inverts the usual relationship between lands and tempo. Most attack triggers ask you to develop your board; this one pays off when you have run dry, turning an empty hand and a tapped-out battlefield into a 5/3 swing. That makes it the rare creature that gets better as the game grinds against you, an answer to a question nobody quite asked: what does an aggressive deck do once it has spent everything? The condition (no untapped lands) reads as a drawback up front, but it dovetails with mana-hungry plans and with sacrificing lands for value, rewarding a board state that other creatures punish you for reaching. Note the limit: the bonus fires only on the attack, so the body is a vanilla 2/3 on defense and a fragile attacker any turn you leave a land floating. The era that produced it treated lands as a resource to spend rather than bank, scattering payoffs around for players willing to tap out and stay tapped out. It is honest about its tradeoff, and the tradeoff is the whole point.