Welcome to my first post for RetroChallenge 2018/04. Carlos Camacho posted in the Coco Facebook group some semi-graphics 3 mock-ups:
Next step will be to add some intelligence to the monsters and decide how much of the game dynamics can be implemented in a tight main BASIC loop that still allows for a challenging game. Here's a video of the original arcade version:
Carlos also sent me a helpful link to the basics of the history of Dig Dug.