Put any bullet pattern or stage similarities you find within Touhou here.
To start off:
DDC Stage 4, red and blue fairy, blue rice and tiny knife spam; TD Stage 4, red and blue fairy spam
Explanation:
The fairies quickly swarm in from the sides, spamming bullets everywhere, dropping tons of resources.
PCB, End of Extra and Phantasm, enemy-less homing bullets; MS, End of all stages
Explanation:
You just have random homing shots from nowhere at the end of these stages.
EDIT: Satori's imitation cards don't count.