The character stops abruptly when attacking, which I couldn't get used to. All attacks need to complete in full, in terms of animation, so it's difficult to have responsive gameplay. Basically, every time you attack you are stuck.
The hit boxes are incomprehensible. Very difficult to judge if you are going to be hit by an enemy or not. This is especially true for the boss. I also found the broccoli hard to avoid being hit by due to this issue.
It makes no sense to me that the bananas would hurt you if they are fleeing away. I think the fleeing banana was a great touch to make the player get an intuition that the instructions to kill the veg was in fact deceptive. Great idea.
The boss was quite obnoxious to fight, as he spawns mob all the time.
I noticed a bug where you can be hit by enemies after you deliver the fatal blow. This made risk taking less attractive.
The art looks great mostly, but there are some poor choices. Default font, default particle system material. These didn't work for the art at all. I loved the art on the UI and the little shadow guy in the background lurking.
Audio was pretty simple. Very repetitive due to how many enemies there are. You may want to use multiple samples instead. So you can randomly pick them as you kill veg.