Mudbutton Torchrunner

Mudbutton Torchrunner is a Pauper-legal common, and that's the format where it sees the most legitimate play — Goblin tribal shells there can loop or sacrifice it repeatedly to stack guaranteed damage. In Commander, it slots into Goblin sacrifice decks like Krenko, Mob Boss or Skirk Prospector engines where you're already generating and expending bodies for value; the guaranteed 3 damage on death scales surprisingly well when you're sacrificing a dozen goblins a turn. In Legacy and Vintage, three mana for a 1/1 with a death trigger doesn't compete with the format's density, so it never appears there outside of niche Goblin tribal lists. Modern is the same story — better redundancy exists at every point on the curve.