This game is quite fun, and pretty well presented! I love most of the sprites, probably with the only exception being the map itself.
I like the idea of an endless QTE survival mechanic, it can be surprisingly addicting to keep up with it!
The one gripe I have about the game is how the player is expected to approach the order of enemies to kill. I have a couple thoughts on this:
I understand the desire to require the player to execute a specific order of buttons/enemies, rather than picking the first one they see. However, it can be frustrating at times. I think this is mostly a result of it not being completely clear which enemy to hit next. There is a window of time before each consecutive kill where I have to deduce which enemy is 'closest', and resizing the sprite is not enough on its own to communicate this intuitively.
I think making it more clear which enemy to hit next would fix this issue, but I also feel doing away with this requirement in the first place might be something to consider as well. Intuitively, with the layout of the level, I feel inclined to take out enemies as I see fit (since they are coming from the four cardinal directions).
The challenge that this contradiction in player motivation versus required action provides could be a great challenge to include but it also might be a hinderance. Ultimately, I certainly can't tell you which avenue would be better, and I'm sure your testing has already guided you to this question and a subsequent answer, but these are just my thoughts.
Overall, a fun and addictive experience with cute sprites :3