This was cool! A very unique concept of blending 2D and 3D. I like the idea of trying to play two games at once. It had me stressed about when the monster would show up. That jumpscare really got me too!
It took me a while to work out I could double jump so I got stuck on the first level for a bit. I'd mention it in the controls of the jam page so people know. Other than that, great work!