In the 6th installment of the Touhou Project series, the player sets out as either Reimu Hakurei or Marisa Karisame to find the secret behind the Scarlet Mist that is enveloping Gensokyo. Their travel leads them to the Scarlet Devil Mansion, where they face off against the inhabitants of the mansion in order to clear the Scarlet Mist from the land.
The Touhou Project games are primarily designated as curtain fire shooters. Players control their character on a 2 dimensional plane and destroy enemies that come from all sides while avoiding bullet patterns of various types to advance through the stage. Each stage has a boss character that has series' of both basic bullet attacks and "spell cards" which consist of typically longer lasting, more complicated bullet patterns.
Play as either Reimu Hakurei --the lone shrine maiden of gensokyo -- or Marisa Karisame --the speedy witch/theif/archaeologist. Reimu has a slower movement rate and does less damage than Marisa but a smaller hitbox and a wider attack range. Both characters have different "spell cards", the equivalent of bombs in most shooters. "Focusing" your character slows their movement rate for more precise movements and alters their attacks to deal more damage over a smaller range.