Inferno © 1984 Williams.

Players walk around a 3-quarters perspective maze shooting at various enemies. After shooting an enemy the enemy's 'soul' (a dark version of itself) attempts to make its way to the top of the screen to an awaiting monster mouth. The player must touch the enemy soul before it gets there or a more difficult enemy is regenerated.

Inferno's maze layout is somewhat similar to Crystal Castles, but without the wide changes in maze height. There seems to be only 3 or 4 'heights' of the maze, which the player can reach via small stairways.