O.S., is a disco-themed bullet hell shoot 'em up developed by Cave and released in 1998. StoryA great military force located on planet Meruto under the command of Admiral Gratze, is attacking the earth in order to gain the most precious material there is, Water.An attacking base was planned on the planet Fever just between Earth and Meruto from which the invasion on Earth should have started. But right before all this, a mysterious energy wave appeared in space and all instruments of Admiral Gratze's fleet where disabled. Because of this accident even the chat between the Admiral and his wife Irene was cut off. Furious about this the Admiral ordered his fleet to land on the source of this wave.Ship Types Fighter Type-APilot: Stephanie Weapon type: Straight shotSpeed: Fast Fighter Type-BPilot: Afro Weapon type: Spread shotSpeed: Normal Fighter Type-CPilot: McCoy Weapon type: Wide shotSpeed: SlowItemsItemDescription Front Power Up Side Power Up Bomb Maximum Power Up Disco Man
