This reminds me of 1988 Amiga game Obliterator, albeit with an isometric perspective and *way* better controls. The title screen has a tough guy with a big gun, the music sounds like it was inspired by Dave Whittaker. Apart from that it's an isometric action game where you traverse warehouses to collect keys, and try to avoid combat when possible. I kind of like it, but the choice of 'warehouse' as a first setting is unforgivably boring.
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