Thanks for the detailed feedback! I'm glad that it is playable enough, it turns out that even with "simple" mechanics of Vampire Survivors it's a LOT of work. :) I feel like I barely got MVP done in time for the jam. Other than the health potion I left on the field at the beginning, they actually only randomly spawn in chests from bosses. They are also not very strong. Definitely something I'll be adding in a future release. I also agree about the invisible walls, they were something I slapped on last minute, ideally I'll have some tile based barriers in place too. I also need to either tweak the spawning or let mobs pass through those, because they get stuck on the other side (currently it just spawns them outside the camera viewport. Also adding a little bit of time in between waves is a good idea. The waves currently change every minute, but they just change mob types and spawn rate, no break. There are of course a myriad of other issues as well. I'm hoping to release an updated version this weekend with a lot of improvements. :) Thanks for playing!