Game is named Demon's Deep so I guess it has something to do with the theme, but the graphics and mechanics don't really scream "underworld" either. It's possible to move around and shoot, but the enemies do nothing at all so there's no reason to bother beside the cool animations. The levels also seem to wrap around after the one with tutorial text for slow motion. Slow motion doesn't seem to have any purpose, too. There's also no music. I'm afraid this feels more like an undercooked demo and is far from a playable game, sadly.