Got duplicate upgrades a lot, would be nice if you could shuffle the list of available upgrades and show the top 4 instead. The blast zones is a nice way of preventing the player from just standing still after getting strong. The X’es that mark where the enemies will spawn make the spawning feel a lot fairer, but still felt unfair at times when a red or yellow enemy spawned close enough to me to cause me to take damage. Range upgrades feels a little too OP, or maybe not having range upgrades is underpowered. I like that there’s no healing upgrades.
Game felt a little bit monotonous over time. The upgrades didn’t stand out in a way that made them fun, and the further I got the less it felt like I was being tested on skill. All in all a fun short game though.