Very straightforward idea and cleanly executed. This is a great jam game. Well done!
At first, I thought this was going to be 'too easy' in that I could just sit in a corner and machine gun down anything that spawns before it could even reach me, but the progression in enemy health here was executed in such a way that you're always just a few hits short and you end up losing guys and it can snowball pretty quickly. It has a nice arc to the whole experience.
I know the game is called "Clickaos", but there should probably be a hold-to-fire option for accessibility. My poor hands can't click continuously like they could before and I couldn't play this for very long because of it. Games requiring buttons spams often don't actually require them to be long term.
Overall, great job on this. Congrats on making something this cool :)