Sanctuary 17 is inspired by the classic Intellivision title Night Stalker and builds on the original mechanics and adds a larger maze with special rooms, more sophisticated robot AI, several inventory items, and a storyline.

More excitingly, it's also a bit spooky... You learn to operate on sound, quickly falling into a tense routine of bringing up your shield at the sound of lasers and returning shots at their origin.
Rock Paper Shotgun