東方Project (Satomi Maiden ~ Third Power)

東方Project is a series of 2D (with 3D background) vertically-scrolling danmaku shooting games made by Team Shanghai Alice

The series takes place in Gensokyo, though there are a few instances where it goes to other places, with the Outside World being one of them.

The series has gained very much of popularity and is extremely well known around the world (much like OTL Mario, Sonic, Grand Theft Auto).