This is a pretty cool concept! Of course some sound would have been nice but it's very well made considering the time constraints you had during development.
It felt like the scaling needed some work, as during the early stages I had expectedly little difficulty, then when the first wave of blue skeletons came it felt surprisingly hard like they were too powerful for the time and number they appeared in, and after that it seems to go on endlessly with no change -- at least up to 20 minutes.
Some kind of factor to scale the monsters by that eventually results in defeat would have added to the survival feel and given some meaning to the clock, like:
- Higher speed over time
- Reduced knockback over time
- Enemies that shoot projectiles, which appear more frequently over time
Something of that sort would have been nice. Overall I had fun though, good job!
edit: I think I won XD
