Good spooky atmosphere with the audio and used 2d assets! I also quite like the fact you made quite a lot of death dialogue, makes it more interesting to die ;) And the lethal onions are a funny idea. Maybe a death sound would've added a lot too.
Gameplay-wise it was a bit difficult for me, I got till the 3rd or 4th challenge (room with many onion). I couldn't figure out how to get past it. Also the controls didn't feel super intuitive to me, I often clicked the wrong mouse button. Maybe automatically picking up the item would help.