I really liked the upgrade system. Strongest sense of progression in the jam I've seen so far. The shotgun is also super fun. The other weapons I tried (pistol and rifle) were very inaccurate and not fun to use. The maps are great looking but the layout is too maze like. It is also hard to tell from a distance if a hall ends in a dead-end or has another corridor. The boss fight at the end was great, loved that it had two special attacks. Very awesome game overall.