Fun! The music was a good fit and I liked the SFX had a good crunch. I like the idea of drones being either mines or friends, but had some trouble choosing, it mostly depended on whether an enemy ran at me or not.
It took me a few play-throughs to realize the white cube was what triggered the level change. At first I thought it was enemies dying, then I thought it was standby drones going away. Only made the connection on my 3rd game.
The level changes were also a bit jarring (coupled with not know what caused them).
Overall I much enjoyed playing!