Stage 4

Stage 4 is part of the recruit's mission to find and destroy the SPASDOT base in Kozankyo.

Stage Context
Like the first two stages, the stage begins again in a neighborhood with the two heading to Kozankyo University's Hirano Hall to speak with the Kozankyo Police Chief. After they arrive, Kagami notices her mother, Kisumi Torisawa, is there. From there, they discuss how Driller was arrested for attempting to join the Shintoist Province and Scarlet Devil of Team Crimson and cooperating with the Kozanese Royal Defense Force after he pled guilty and agreed to cooperate with the military as part of his plea. The chief then orders the duo to assassinate the leader of SPASDOT, Frederic Sam Fawkes at a stronghold located within Kozankyo. After the duo leaves Hirano Hall for the stronghold, they are stopped by Ayako Sugiwara who tells Driller that 'Maribel' wants him to rejoin the SSC. Driller declines and agrees to challenge her in a danmaku duel, which she subsequently loses. After losing, she flees to the nearby shrine to pray while Driller and Kagami continue on with their mission.

Background
Like the first and second stages, it again takes place in a neighborhood, but unlike their boss stages, the boss fight takes place at Kozankyo University instead.

New enemies

 * Boss Crimsonite Grunt
 * Remikaze

Opponents

 * Tanker (name not official)
 * Ayako Sugiwara (boss)

Deaths

 * Numerous Boss Crimsonite Grunts - Killed by the duo for trying to stop them from progressing.

Strategy

 * This is the part where the game will start to get harder and harder. The main focus are the Boss Crimsonite Grunts, which repeat the same pattern over and over. When you get to parts where there's multiple, they can get very dangerous if you don't kill them quickly.
 * The Remikazes will pursue you and then detonate themselves when they get close to you. No matter whether you kill them or not, they will spew the same danmaku upon death.

Behind the Scenes

 * The room 304, which Driller jokes on it being room 404 where nothing can be found is a reference to the HTTP error 404 Not Found.
 * The shock given to Driller and Kagami when the Kozankyo Police Chief orders them to kill Fred Fawkes is a reference to the 2014 film The Interview, where a similar shock can be seen when the two characters are ordered to assassinate Kim Jong-un.
 * The person of 'Maribel' and the SSC is a reference to Maribel Hearn and the Secret Sealing Club, which is another example of Touhou Project material being referenced as humor.
 * This is the only stage to have more than one pre-battle cutscene, most likely because of its length.
 * This is the first stage to have humanoid enemies.