Black Dig Dug's looks like Taizo, but his armor is purple and his helmet has a red horn on it. He has a green drill.
Black Dig Dug has the same abilities as Taizo, including a same device like Taizo's Harpoon-Drill. He can dig in any direction, and if he sees the real Taizo, he'll shoot his drill at him and pump him until he pops. If Taizo shoots his Harpoon-Drill before Black Dig Dug does, a button appears above them pushing at each other to get through him.