OrangePixel's original Groundskeeper was more of an experiment than a full game, an endless survivor-shooter in the company's typical old-school 2D style. The sequel retains the look and feel, but everything has been expanded: there's now a full story behind the tiny compartmentalized levels, you have access to a staggering amount of weapons, and the graphics and on-screen action have been given a considerable boost.
The game features the developer's usual calling cards: retro basics dialed up to 11. At the core it's a Contra-style shooter, but the sheer chaos of dozens of enemies and attacks on screen at once combined with impressive speed means it also has a bit of "bullet hell" DNA as well. Granted, most of those bullets are yours: your character zips around the small stage shooting everything that moves with a variety of crazy guns, lasers, rocket launchers, air bombs (where's she hiding them?), and other assorted tools of localized destruction. You will die eventually, but how far you get and how many enemies determines how well-equipped you are in the next round. Just think of it as a "roguelike" with lots and lots of explosions.
Groundskeeper 2 includes support for SHIELD, MOGA, Xperia Play, and Green Throttle controllers, and considering the amount of action on-screen at once, dedicated gamers will probably be happy for the inclusion. In typical OrangePixel fashion, the $2 game has no in-app purchases.
Update: There's also a free version of Groundskeeper 2 with advertising. No in-app purchases in this version, either.