This game fits the theme very well.
Once I got that ricochet upgrade, there was no going back, my lab was not salvagable... Oops.
I do think there's an issue of conveyance. For example, I didn't understand why the bullets started ricocheting in later levels, when I never chose the ricochet upgrade. Can you make it more clear that every upgrade is paired, so it comes with a pro AND a con?
Can you include some way for a player to check what the controls are? I bought the "pause fire" upgrade and promptly forgot which keybind it is and had no way to check. It could be in the corner of the screen at all times, or on a pause screen.