Arcade versionIn the coin-operated version the game ends on round 256 (shown as round 0) since this board is unplayable. At the start of the level, a Pooka is placed directly on top of where the player starts, with no way to kill it. This is a famous example of a kill screen (a area of a game that is impossible to play, usually caused by the oversight of developers.)
ReleaseDig Dug was one of the "Fabulous Eleven" launch games for the Atari 7800.
Information also contributed by PCGamer77 and Nélio