Thanks for checking it out, completely agree with level 5! I was hoping someone would talk about it too; I rushed the design due to time, I think it's the weakest point of the game and I'd really like to fix it up post-jam. My intention was that players would switch between their visible/invisible states while inspecting it with the looking glass, but I think that's just far too obscure to expect anyone to pick up. It also looks like a terrible mess, and the solution is easily forced.
It's funny cause I think your guys' puzzle game is actually far better hahah; I'm still looking for some time to go back and replay your last level!