A very ominous dungeon! Good lighting effects and sound effects to sell the environment (though the sounds seemed a little too quiet to me). I'm not sure who they hired to install those floor spikes, but surely that's an OSHA violation or something keeping those around...
I think I'd suggest adding some more gimmicks or puzzles to the exploration next time to engage the player more than just walking around (maybe some buttons to press to open doors or something!)