Well done on the submission! I enjoyed the 404 over-scoping text; made me laugh!
This is a good idea in concept. Having to figure out how each prank is meant to work and getting them all completed as fast as possible is a fun game-loop.
Other than the general missing content (that you're aware of based on the 404 text), I think that a visual of what items I'm carrying would really help. I had no idea if I had picked an item up most of the time.