i ended up reaching level 15 in 267 seconds and had lots of fun with this game! Some little notes:
- items/abilities upgrades don't have any indication of current level. like 1/3, 2/3 etc
- abilities dont have tooltips, so i had no idea what they actually did
- onwards from level 13, the game started being a little laggy. i assume thats because of increasing slime count?
- the main menu font doesnt really fit the other ui elements
i really liked how smooth the ui is and the transitions as well. Great job!