An absolute gem of a game, and can definitely be counted as one of the successes of Early Access. And let me tell you, as long as we get games like Assault Android Cactus, the bloody system can stay.
At its core, Cactus is a twin-stick shooter and ranks among the best of them, if you ask me. Large enemy variety, level variety, even completely shifting, dynamically-evolving stages, this game has it all. The game is relatively easy if you just want to win it (although the bosses will require you to git good), but getting high scores or at least decent ranks? Oh, boy, now there's a challenge.
Not least impressive is the variety of adorable combat androids you can take into the fight. The best thing is, they're not just skins, but each has her own combat style. From the starring Cactus, who wields an assault rifle and flamethrower combo, to the likes of Aubergine, whose main armament is a little pet robot she sends in to slice enemies (one of the more challenging androids you can play as). Each Android even has different dialogues when they meet bosses and such.
The thing even has co-op, though it is one of the local variety.
Overall, Assault Android Cactus is a great game, well worth its asking price. So go grab your railgun and get ready to obliterate some robots!