Rosie

Rosie is one of the two types of Big Daddies. It carries a rivet gun and throws proximity mines if it's far enough away from you. It has a second form called Elite Rosie. The Elite Rosie has a big, red collar. It is taller but slower than the Bouncer. They appear on the levels Neptune's Bounty, Arcadia, Farmer's Market, Olympus Height, Apollo Square and Point Prometheus.

In order to reach Frank Fontaine, you disguise yourself as a Rosie after collecting parts of the suit.

The Rosie takes its name from Rosie the Riveter, a WWII-era American cultural icon.

In the BioShock 2 gameplay video "Hunting the Big Sister", The Prototype Big Daddy can see his reflection in the water, his helmet is that of a Rosie although it was later confirmed that this was only a placeholder image. The Rosie will also return as another playable Big Daddy. While playing online, the BioShock server will randomly place a Rosie suit inside the map. The first player to find and touch the suit will become a Rosie Big Daddy. You will be granted extra strength and the Rosie's choice of weapons. However, you will not be able to use plasmids while in the suit and while wearing it, you risk the fact of being targeted by enemy players since you are more powerful.

Strategies
One of the fastest ways to defeat a Rosie is to freeze it with Winter Blast or Frozen Field. Also effective is to use electrical attacks such as Electrobolt, the Chemical Thrower with Electric Gel, or the Shotgun with Electric Buck. This sends the Rosie into a state of shock in which it cannot attack. Rosies are vulnerable to armor-piercing ammunition from the Pistol or Machine Gun. The fire bolts of the crossbow are also are very effective way of dealing a lot of damage per shot.

A satisfying and resource-efficient way to deal with a Rosie is to grab an object with Telekinesis. Run up to the Rosie to the point where it throws Proximity Mines at you. Catch these mines with the object and throw it back at the Rosie, causing the mines to explode upon impact. For a minimum amount of EVE you can either kill or severely damage the Rosie with this strategy.

Another resource efficient tactic is to use telekinesis to pile a number of red barrels (at least 4) in one spot, preferably in the path of a big daddy, and then place a corpse on the other side. This means that when the Little Sister passes to the corpse the Big Daddy will walk through the barrels too, when the Big Daddy does this fire a frag grenade at the barrels and the resultant blast will take at least 3/4 of the daddy's health off leaving you to mop up. This is particularly useful for the first Big Daddy in Neptune's Bounty.

Another good strategy for many Rosies is to use Hypnotize Big Daddy on them, and then bring them to an area with a Security Camera, and use Security Bullseye. Depending on the area, the Rosie should have one half or more of its life taken away, without angering it. Wait afterward, however; if it doesn't get another Little Sister before being angered, then the whole endeavor is fruitless. This does not work on Bouncers because Bouncers are inadequate at taking out security bots, and are usually killed before the alarm is over.

The most overall efficient way to kill Elite Big Daddies is to shoot them with a steel tipped Crossbow bolt, hit them with Electro Bolt, and repeat the process until they are dead. This is much cheaper than most other methods, and does not require weapons upgrades to function, but upgrading the Crossbow damage is highly beneficial. To do the above strategy, you must fire and stun as quickly as possible, as you only have fractions of a second to act while the Big Daddy is immobilized.This tactic was researched on Elite Bouncers and Elite Rosies, and is more effective on the Bouncers because they take the shortest possible route to you.

A relatively simple and effective way to kill Big Daddies is to shoot Exploding Buck Shot. On Easy mode, 3 shots should kill it.


 * A strategy more useful on Bouncers than Rosies is, hack some kind of hackable device, but instead of completing the hack you direct the flow to a alarm tile and when the security bots come after you, you shoot the Security Bullseye plasmid on the Big Daddy, on Hard this strategy may need to be used twice to kill the Big Daddy, and the two main benefits of this strategy is: it is cost efficient, and it keeps you out of harms way (be sure that the Big Daddy has summoned a Little Sister or the tactic will only bring you money and (with level 4 Rosie research) rare inventing materials).

There seems to be a tank on its back which can be damaged and forced to leak gas (possibly oxygen), much like when the valve is taken off the tank on a Bouncer's back. By shooting the gas cloud or igniting it with the Electro Bolt or Incinerate! plasmid it is possible to deal a considerable amount of damage to the Big Daddy without using much EVE or ammunition.