
Yousei Daisensounote ~ Touhou Sangetsusei (more commonly known as "Fairy Wars") is a video game created by Team Shanghai Alice for Windows computers in 2010. It's the 12.8th videogame installment in the Touhou Project franchise, and a spinoff of the Touhou Sangetsusei manga series.
Cirno's house got destroyed by the Three Fairies of Light, and since Cirno took it as a declaration of war, she's going to punish them.
The game features the freezing mechanic. Cirno can freeze bullets that come into contact with ice used by her, and frozen bullets that touch other bullets will freeze them too. The bomb system has also been revamped into the Perfect Freeze mechanic, allowing all bullets on the screen to be frozen.
This game provides examples of:
- Art-Shifted Sequel: The game's character portraits are in a drastically different art style from the other shmups. It's much more expressive, has more vibrant colors, and puts a lot of emphasis on the characters' clothes. They were drawn by manga artist Makoto Hirasaka.
- The Battle Didn't Count: Played for Laughs. The Extra Boss deliberately lowers the power of her attacks in order to humour Cirno, and while they're both exhausted after the fight, Cirno is the one who gets the "battle-damaged" portrait normally reserved for the loser. She's still shocked at how long Cirno was able to keep going, though.
- Collision Damage: Unusually for the series, this is averted for most Mook-level enemies. Touching a boss or miniboss will still harm Cirno as normal.
- A Day in the Limelight: For Cirno, who gets her own game after being a stage 2 boss in another game and being a playable but non-main character in several other games.
- Flawless Victory: You're given golden medals for capturing cards without taking damage, bombing or freezing any bullets. That was probably ZUN's idea of a joke.
- Game-Breaking Bug: Hitting Retry from the pause menu on Stage C2-2 or C2-3 and then subsequently beating the game on route C2 without returning to the menu would crash the game. This one has not been patched.
- Haughty "Hmph": At one point Cirno arrogantly goes "hmph".
- Insane Troll Logic: At the final battle in one route, Cirno accuses the Three Fairies of playing dirty by fighting three on one. According to the them, however, the three of them always act as a single unit, so it's a fair one on one fight. Furthermore, it means previously Cirno has been fighting one on one-third, so she was the one playing dirty. Cirno being Cirno, she fell for this.
- Life Meter: In place of lives, Cirno has a "Motivation" percentage which increases as she performs certain actions, and produces a Game Over if it falls under 0%. Getting hit by a bullet reduces Cirno's Motivation by 100%, and the Extra Boss can also project fields which drain her motivation over time.
- Literary Allusion Title: "Yousei Daisensou" (The Great Fairy War) to "Youkai Daisensou" (The Great Yokai War).
- Lower-Deck Episode: This is a much shorter game than usual, focused on a quarrel between Cirno and the Three Faeries. Every single person in the game is a fairy, with Daiyousei, Lily and the Three Faeries themselves as bosses, rather than any of the usual "A-list" cast members. Except at the end of the extra stage, where Cirno takes on Marisa.
- Nerf Arm: In order to go easy on Cirno, the Extra Boss Marisa uses a variant of her signature Master Spark that's powered not by her normal elemental furnace but a flashlight.