Gensokyo Tower Defense
- Main article: Gameplay
The player (as Reimu Hakurei, Marisa Kirisame, or Sakuya Izayoi) builds small towers that fire bullets at the enemies attempting to get from A to B, much like other TDs. Most enemies can't pass through towers, allowing you to make mazes and maximize the time they're with in the firing range of your towers. On anything other than Easy mode, there are two sets of enemies: one going from top to bottom, the other going left to right.
Gensokyo's small fry have come to violate the Scarlet Devil Mansion, and it's your job to stop them. That's about it.