Traxos, Scourge of Kroog is a rare Legendary Artifact Creature — Dragon Construct card from Dominaria Promos (PDOM), collector number 234s. Current market price: — (foil $1.98), TCGplayer market prices via Scryfall.
Trample Traxos enters tapped and doesn't untap during your untap step. Whenever you cast a historic spell, untap Traxos. (Artifacts, legendaries, and Sagas are historic.)