I've gotta admit, I had a lot of fun playing this one! The punching was really satisfying, and I felt the urge to try again every time I died. When you're playing a game, it's really important to feel that sense of replayability, and this game nailed it. I also think the sound effects and music matched perfectly - good choice!
I do think the game could benefit from better graphics. While the simple style got the job done, I think more detailed and immersive graphics could help the game. In addition to the graphics, adding more polished animations and smoother transitions is never a bad idea. I understand the jam's time span makes it a lot harder to do these things, but even the smallest bits of polish can change how an entire game feels!
Overall, this game was a ton of fun and I enjoyed playing it. Good luck, and keep up the great work!