Thanks for playing my game and for the good feedback.
I will try to implement some sort of story or level progression, and I do need to figure out a way to make endless mode harder without just increasing numbers, since the game can only handle so many hundreds of boxers.
I'm currently working on more levels, so hopefully that'll solve the content issue.
But I'm glad you found it fun, this was just meant as a tutorial game to teach myself coding, it's encouraging to see some people having fun with it.