I actually fleshed out a full concept for the game Leon plays here. Basically starts as mix of Dig-Dug and Pac-Man. You keep digging down further and further to find treasure in mini-rooms, all while getting chased by the scrapper creatures. It gets more complex the deeper you go, since there are multiple routes and exits. I honestly love the idea so much that, if I were to make a small-scale game, this would probably be it!