The Rosie is one of the functional types of Big Daddies in Rapture, along with the Bouncer, the Rumbler, and the Lancer. Along with being assigned to protect Little Sisters, Rosies are also the supplementary mechanics and maintenance workers of Rapture. Its main weapon is a giant Rivet Gun. They are taller and slower moving than the Bouncer, making them less agile, but their long-range gun makes them just as dangerous.
The Bouncer is one of the five functional types of Big Daddies, along with the Rosie, Rumbler, Alpha Series and the Lancer. Bouncers are more agile than Rosies, but are entirely ineffective in ranged combat. The Bouncer’s main weapon is an over-sized Drill (and, in the case of an Elite Bouncer, spinning the harpoon) attached to its right arm and powered by the internal combustion engine on his back. Generally They attack using powerful blows at close range, with a fast charge being Their only long range offensive ability.