Overall: I think it's pretty cool that your combo is also your health! I really enjoyed the concept of this one, and the gameplay loop is satisfying. The game ramps up in difficulty at an appropriate rate, and the graphics + audio combine really well to make the game feel good. My biggest complaint is that there didn't seem to be a "game over" screen of any sort, so I had to Alt+F4 to close it, and there wasn't any metric of score, so I can't boast at how well I did, or replay the game with a visible high score to beat.
Fun: I enjoyed it! I definitely had a good time running around and dodging everything . As stated, any indication of how well I'm doing would be nice. Either a timer, or score, or "longest combo at 9 without dropping"... anything! It would add replayabillity for sure.
Innovation: Top down shooters are definitely a genre in need of innovating, and I like your combo = health addition! I think it can make the game too easy at times, but since it's the tie in with the theme, I can't complain. Speaking of...
Theme: I really like how the combo is the center of attention. It's very clear that the combo is the main focus of the game, and it's a pretty great take on the theme.
Graphics: First things first, I love the screen shake. I like the gore, but making it pink is an interesting touch. I think the background is a bit awkward? I can't tell if it's grass, or a nuclear river of some sort. The grey boxes are also a bit out of place.
Mood: I usually reserve this space to talk about the emotions I felt playing the game. It's fun, and over the top, and goofy, and that's great.
Audio: I like the sound effects. Some music would be nice.
Humor: Good ol' nonsensical violence. I'm a fan.
Final Thoughts: Checking out your Itch.io page, this looks like it's your second game jam? And dang, it's a solid entry. Great work!