In Terraria, how much space is required for a fire imp to spawn/teleport? So far, I've kept my hellstone mine restrited to either 3 tiles high or 2 tiles wide, and I haven't had any trouble until I attempt to mine a large patch of hellstone. So what is the minimum required space for an imp? It must be more than 2x3.
From the Terraria Wiki
Just be sure to fill in some of the hellstone you mine to keep the imps from spawning.