The Big-O-Blaster (better known as B.O.B.) is a doomsday weapon built by Mingella and Blobbelda in Banjo-Tooie. The machine can suck the life force out of anything shot by its energy beam, reducing objects to a monochrome state and zombifying living creatures. This process also works in reverse, providing there is enough life force stored for the target.
Mingella and Blobbelda intended to restore their skeletal sister Gruntilda to full life after she was defeated by Banjo and Kazooie and trapped under a boulder for two years. Once rescued, Grunty used B.O.B. to suck the life force from King Jingaling and his palace; however, since Gruntilda's body was somewhat less than slim, Jingaling's life force alone wasn't quite enough. She decided to blast the entire Isle o' Hags, which was possible, but only after a charge-up that took so long that Banjo and Kazooie reached Cauldron Keep before it could fire. Once the pair beat back Grunty and her sisters, Kazooie restored the life force to Jingaling's palace and also Bottles, who was killed much earlier. Where the "extra" life force that saved Bottles came from is unknown, though it's possible that the amount that had been charged by the time Banjo and Kazooie reached the machine was enough to revive Bottles.