This was a delightfully charming little game! The puzzle mechanic was surprisingly well-handled with some really good depth, and there was some really creative use of those simple-on-paper systems, such as having a full on boss fight incorporating the different movesets. Honestly, a really stellar idea, with some awesome execution.
Having the guards to show that you can bypass 2d and 2.5d enemies using those modes, only to then have them turn up in the final boss fight, is a really smart move - and it lands really well here. The humour is sparse enough that it doesn't overstay it's welcome, while still having enough lightheartedness to land the punchline when it does appear.
My only critique is maybe the sound design - which is likely a product of the time limit - but it does add to the charm, and while it might not be my cup of tea it definitely fits the vibe of the game.
For a four day project, this is really impressive, and really well put together. Nice work!