A few things I enjoyed:
- The diversity of weapon types.
- The pursuit of many goals (find key, find door, find wand, destroy enemies, avoid enemies).
- The urgent feeling of needing to find the goal before I became swarmed by monsters.
A few changes I would suggest:
Different enemy behaviors, and less enemies. The only weapon I ended up using was the shotgun. That wasn't because it was the best weapon to counter the enemies at hand: a large horde of slow moving enemies. Having different enemy types that have strengths and weaknesses to different weapons would make the game much more engaging and force players to use a balanced mix of the weapons as well as providing an incentive to not lose any of them. For example, if there was a ranged enemy, the sniper would be preferable to take it out, but if I lost the sniper, I'd have to readjust my tactics to take it out at a closer range. The presence of less enemies allows the player to actually form a tactic other than "run n' gun" and consider how their current loadout affects the situation. Less enemies would also help with the lag problem.
I also noticed that the door will spawn behind a wall--or that it didn't, in fact, spawn in the first place.
Great start, I enjoyed the playing experience! I think that the presence of more unique enemies would help the game stand out from the current crowd of horde survival games. Good luck with whatever you decide to do!