It took me a death or two to figure out what I was doing but once it clicked I was all in. The ammo being tied to your health was a nice touch. For whatever reason it took me forever to realize you could pick up guns and once I did that's when the real fun started.
Solid variety in enemy types, game play is simple but it has that addicting quality to it. My only negative is that once the screen started to get full and bullets were flying everywhere the game had a seizure and glitched out, so i couldn't see anything lol. But I kept shooting anyway until I died, then once it reset everything worked again.
All that to say I really enjoyed this.