Adding to the commets that this is an excellent concept and great game. I had fun with the game. A few things got my attention:
- I felt the AI a bit passive at times. I noticed that there is some idea on what it is doing but usually it was not on the agressive side.
- I think that it would be cool if the enemies that are holding keys are visually distinctive. I've spent too much time on looking for one gold key :D
Did you have more ideas on enemy behaviours and types?