Rosie

The Rosie is one of the four 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 yet slower moving than the Bouncer, as well as more agile, making them more of a threat.

BioShock


Starting in Olympus Heights, the player will begin to encounter Elite Rosies, which are significantly more powerful than their original counterparts, and with nearly double their health. The Elite Rosie has a large, red collar. A collarless Elite Rosie corpse can be found in the left storage room of a restaurant in the Farmer's Market. The regular Rosies appear in Neptune's Bounty, Arcadia, and Farmer's Market. Elites appear in Olympus Heights, Apollo Square and Point Prometheus. During the opening level of BioShock, a Rosie is briefly seen doing electrical work in a connection tunnel, and later, one is seen briefly in the Proving Grounds in a scripted fight with a Splicer, where it is crushed and killed by an overhanging skeleton of a whale.

Rosie "Moods"
The Rosie, like the other Big Daddy types, has three "moods" that may occur when the player encounters them. These moods appear as the color of the portholes on the Rosie's helmet.
 * Green light: A Big Daddy under the effects of Hypnotize Big Daddy will radiate a green light from their portholes. These Big Daddies are friendly to the player, and will protect them as if they were a Little Sister.
 * Yellow Light: A Big Daddy with yellow lights emanating from its portholes is neutral to the player, and will not attack them. By default, unscripted Big Daddies always start out in this mood. Some scripted Big Daddies spawn in other moods, but this is just for the purpose of effect.
 * Red Light: A Big Daddy attacked by the player or under the effects of Enrage will produce a red light. In the first case, the Big Daddy will attack the player. In the second, it will attack anyone in its vicinity including the player if they are the closest to the Rosie.

Attacks
When in combat, the Rosie will produce three different kinds of attack:
 * Shoot: The Rosie's basic form of attack, where it shoots the target repeatedly with its Rivet Gun.
 * Mine Throw: If an enemy approaches the Rosie, it will start throwing Proximity Mines at the target.
 * Push: If the Rosie's foe is at melee range, it will push them away with their Rivet Gun, dealing medium damage.

Strategy
While many strategies may apply equally well to all Big Daddies, each type has their own particular characteristics worth noting, which may lead to specialized tactics.

General

 * Always ensure one has full health, as well as a reliable supply of First Aid Kits, EVE Hypos and ammunition before fighting a Big Daddy, as these are one of the toughest enemies in the game.
 * It is recommended to study a Big Daddy's path and stalk them, so as to attack them where the player has the biggest advantage. Study the environment as well, so as to be able to formulate a winning strategy.
 * Armor-piercing ammo (for Pistols and Tommy Guns) deals more damage against Big Daddies than standard and Antipersonnel ammo.
 * Always ensure one has complete control over the fighting area (i.e. the place is clear of Splicers and all Security Devices have been hacked or destroyed). Loss of control might signify defeat in the later stages of a fight.
 * Never take on another enemy while dealing with a Big Daddy, except in some unique cases (see below). If the player is forced to fight another enemy, take it down first and come back to the Big Daddy.
 * Little Sisters always stop to drain ADAM from any nearby corpse they find. Corpses can also be moved by the player, enabling them to choose where they want the Big Daddy they're targeting to halt.
 * Piling up several explosives onto a Big Daddy's path (preferably on top of an oil slick) and blowing it up at the right moment is a cheap and effective way of killing, or at least severely injuring, a Big Daddy. If the enemy survives, they will be on fire, which will drain their health continuously.

Rosie

 * Keep in mind that Rosies are the most heavily armored enemies in the games, more so even than Bouncers. As such, be ready for a prolonged fight, and try to completely isolate the Rosie from its surroundings before attacking.
 * Rosies are very accurate shooters, and are capable of dealing heavy damage if the player isn't careful. Always try to attack a Rosie where there is plenty of cover to be found, and avoid open spaces.
 * When at mid-range, always stay on the move, as the Rosie will start throwing Proximity Mines at the player.
 * Moving in a circle around a Rosie at close ranges will greatly decrease its chance of hitting the player.
 * Although Rosies aren't as specialized in melee combat as their Bouncer counterparts, they are still capable of inflicting a severe amount of damage to the player and will knock them back whenever possible. As such, use stunning Plasmids when attacking the Rosie at close range.

General
By the end of the alarm, the Big Daddy will be either severely weakened or dead, without the player risking themselves at any point. Note: This strategy is more effective on Bouncers as they cannot destroy Security Bots unless they stray too low.
 * Hypnotize Big Daddy is, obviously, a prime choice when faced with a Big Daddy, as it turns the hulking creature into the player's bodyguard. It can also be used to pit two Big Daddies against each other, which is both an entertaining and effective way of killing them.
 * Enrage can be used in a similar fashion: by Enraging a Big Daddy, the player can clear an entire room to a minimal cost in EVE. Make sure one is at a distance, as the Big Daddy may assault the player if they are the closest to them.
 * Incinerate! is recommended against Big Daddies, as a single cast will drain a significant portion of their health over time.
 * Telekinesis may come in handy if there are explosives lying around. It can also help the player formulate various different strategies (see above and below).
 * Electro Bolt will temporarily stun the Big Daddy, as well as deal increased damage (especially in water). Do not attempt to One-Two Punch the Daddy unless one possesses the correct Gene Tonics, though, as the Wrench deals only quarter damage against Big Daddies.
 * Insect Swarm will distract the Big Daddy as well as deal continuous damage, allowing the player to take potshots at it.
 * Winter Blast can help the player quickly dispatch a Big Daddy, as it stuns them and reduces the amount of damage needed to destroy them. However, their corpse will shatter, leaving no loot.
 * Security Bullseye can single-handedly take down a Big Daddy if the player performs the following strategy:
 * First of all, hack a nearby machine and direct the flow towards an Alarm Tile.
 * Paint the target Big Daddy with Security Bullseye (Note: as this deals no direct damage, this won't cause the Big Daddy to attack the player in any way).

Rosie

 * Telekinesis is more effective against Rosies than Bouncers, due to the increased number of possible strategies:
 * One can use it to create movable cover and a shield by picking up and holding a large, solid object.
 * By approaching a Rosie and firing its Proximity Mines back at it, the player will be able to kill them without receiving any damage, and at a minimal cost in EVE.

Recommended Weapons and Ammunition

 * Electric weaponry such as Electric Gel and Electric Buck are the best form of ordnance against Big Daddies: not only do they deal much more damage against them than with any other ammo type, but they also temporarily shock Big Daddies, stunning them. The constant stream from the Chemical Thrower loaded with Electric Gel will freeze the Big Daddy in a stun lock, rendering them powerless unless the Chemical Thrower runs out of Electric Gel. This is the easiest way to kill a Big Daddy, so long as one has the right amount of Electric Gel.
 * Armor-piercing ammo also deals increased damage against Big Daddies, although not as much as electric ammunition.
 * Although the Wrench only deals 25% damage against Big Daddies, if fully upgraded with the right Tonics it is still capable of dealing very high damage against them, especially when used in conjunction with Electro Bolt. On Hard, it takes a maximum of five One-Two Punches to kill any Big Daddy on any level.
 * Exploding Buck deals very high amounts of damage and sets the target on fire, making it a very good choice in this type of fight. On Hard, no more than six shots are required to kill any Big Daddy on any level.
 * Frag Grenades and Heat-Seeking RPGs, because of their high damage output, are a useful tool against Big Daddies. Note: If tackling a Bouncer, it is better to have the upgrade that renders the player immune to self damage, otherwise one may end up losing a lot of health.
 * Proximity Mines are incredibly versatile when it comes to Big Daddies. One of the most popular strategies involves attaching several Proxy Mines onto a physics object (preferably an explosive) and firing it at the target Big Daddy using Telekinesis. This is called an "Anti-Big Daddy Bomb", as it usually ends up killing or at least severely weakening the aforementioned victim.
 * Napalm, although not as effective as Electric Gel, is nevertheless capable of taking down a Big Daddy in a couple of seconds.
 * Liquid Nitrogen presents the same characteristics as Winter Blast, and both can be used interchangeably.
 * Although headshot bonuses do not apply to Big Daddies, Steel-Tip Bolts and Incendiary Bolts (especially the latter) are still capable of dealing high amounts of damage to Big Daddies. On Hard, a maximum of six Steel-Tip Bolts or five Incendiary Bolts are required to kill any Big Daddy on any level

Recommended Tonics

 * The Armored Shell line of Tonics will significantly reduce damage received by a Big Daddy's attacks, making this a very useful Tonic to have during combat.
 * EVE Saver will reduce the cost in EVE when casting Plasmids.
 * The Damage Research line of Tonics will significantly increase damage dealt against enemies researched using the Research Camera. The effectiveness of this Gene Tonic is entirely dependent on how much research the player has done.
 * The Medical Expert line of Tonics will help the player save up on First Aid Kits.
 * The Electric Flesh line of Tonics, in addition to making the player resistant or even immune to electrical damage, will significantly increase the effectiveness of all electricity-based attacks.
 * The SportBoost line of Tonics will make it easier for the player to run for cover as well as dodge the Big Daddy's attacks.

Becoming a Rosie
When Jack finally confronts Frank Fontaine in Point Prometheus, Fontaine barricades himself and escapes to the Proving Grounds and later, his personal lair. In order to chase Fontaine down, Jack is forced to don a Big Daddy suit and undergo modifications that trick Little Sisters into thinking he is one of their protectors, making them open the doors in the path to Fontaine.

Jack is required to equip a helmet, a bodysuit and a pair of boots. Despite the fact that all functioning Big Daddies in the level are Elite Rosies, the only bodysuits which are available belong to the normal Rosie model, so Jack has no choice but to wear those. He also performs an automated vocal cord surgery and applies three pheromone samples on himself, making him both sound and smell like a real Big Daddy. After that, Jack enters the Proving Grounds with the help of a Little Sister (or multiple Little Sisters, if the initial one is killed), protects her when she gathers ADAM in the area, and eventually reaches Fontaine's lair.

Jack's transformation into a Rosie is not complete, however, as he does not have his skin and organs grafted into the suit and he is able to take off the helmet after entering Fontaine's lair. Jack never wears the Rosie's gloves, and he is never given the strength to pick up the Rivet Gun either. The process gives him an extra resistance to damage, though.

BioShock 2
Rosies return as an enemy in BioShock 2. In the Single Player campaign, it has exactly the same traits as in the original game. Rosies in BioShock 2 have a slightly altered appearance. Whereas their diving suits were a bright orange in the original, they look duller and dirtier in the sequel, as the suit has worn down over time. Rosies are only encountered in Pauper's Drop. Before then, a Rosie is seen on the seafloor outside of Adonis Luxury Resort riveting a leaking window, repairing it in the process.

Strategy Changes

 * Big Daddies will now attack the player if one stays too close to their Little Sister for a prolonged period of time.

Recommended Plasmids

 * Security Command can still be used to take down a Big Daddy, but only if the player has landed the needle on a red area while hacking.

Recommended Weapons and Ammunition

 * Since Subject Delta's arsenal is completely different to that of Jack's, the same strategies cannot always be applied (with the exception of some cases where two ammo types are identical in function). However, Big Daddies still remain vulnerable to armor-piercing and electrical attacks.
 * Upgrading the Drill so that it deals added damage versus armored foes makes it a palatable choice in a Big Daddy fight.
 * Heavy Rivets always deal more damage than standard Rivets, and should be considered equivalent to armor-piercing ammunition in this case.
 * Phosphorus Buck deals a high amount of damage and sets the target on fire. This makes it an effective weapon against Big Daddies, especially if used at the beginning of a fight.

General

 * The Armored Shell line of Tonics will significantly reduce damage received by the Rosie, making this very useful to have during combat.
 * The EVE Saver line of Tonics will reduce the cost in EVE when casting Plasmids.
 * Medical Expert will increase the player's First Aid Kit carrying capacity by one, thus allowing the player to endure longer battles.
 * EVE Expert will increase the player's EVE Hypo carrying capacity by one, thus allowing the player to endure longer battles.

BioShock 2 Multiplayer
In multiplayer, a player can pick up a Big Daddy Suit to play as a Rosie for one life. The weapon wielded by the player is the Rosie's Rivet Gun. It has infinite ammo, but firing continuously for too long will cause the rivet gun to overheat. A quick-melee attack can be performed with the rivet gun. The player also has access to two other Rosie abilities: Rosies only have two different "moods" in multiplayer, indicated by the light emanating from their portholes:
 * Big Daddy Stomp: the Rosie can perform a stomp attack, which stuns all nearby enemies.
 * Proximity Mines: the Rosie is equipped with a total of six proximity mines to deploy around a map.
 * Blue Light: indicates the Rosie is friendly to the player.
 * Red Light: indicates the Rosie is hostile to the player.

If Playing As A Rosie

 * When faced against large groups, make each Rivet Gun shot count, as firing repeatedly will cause the weapon to overheat.
 * Always prioritize enemies with the Nail Gun and the Grenade Launcher, as they are the ones most capable of harming a Big Daddy.
 * Charging into the enemy is actually a rather valid strategy. Not only does this have the effect of completely scattering an enemy group, but it also enables the Rosie to get into Stomp range, and thus stun every foe around the player. Big Daddies cannot replenish health, though, so quick thinking is required.
 * Although Rosies possess a large amount of health, they are capable of dying very quickly if faced with many enemies at once. If on a team, stay close to allies which will use the Big Daddy as a bodyguard as they hunt for enemies. If alone, use defensive tactics and avoid entering large areas if unsure of their safety.
 * Rosies only have six Proximity Mines, so avoid throwing them at random. The best way to use a Proximity Mine is to either set it as a trap, or throw it in the middle of a group of enemies. Recommended trap locations include:
 * Doorways and narrow passages. Always place the Mine in the direction opposite the general enemy location, so that they won't be able to spot the Mine until they pass through, which will be too late. Do not place the Mine too far from the passage, as it will increase the chance of its detection.
 * Near explosives. This can create deadly explosion chains which are more difficult to avoid.
 * Directly on a Vending Machine. Most enemies won't notice the Mine until they are in direct contact with the machine.
 * If protecting the Little Sister, scout ahead to check for incoming enemies while she's feeding on a corpse.

If Fighting A Rosie

 * Electro Bolt is the best choice when faced against a Big Daddy, as it will deal a good amount of damage against them as well as stun them.
 * Alternatively, picking up an explosive with Telekinesis and firing it at the Rosie will also deal high damage, as well as set the Big Daddy on fire. This Plasmid can also be used to send a Rosie's Proximity Mines back at it.
 * Always coordinate with nearby teammates (or enemies, in free-for-all game modes) when fighting a Rosie. Try to attack the Big Daddy from multiple directions and immobilize it.
 * In free-for all game modes such as Survival of the Fittest or ADAM Grab, a Rosie in the level is the top priority. Fail to team up against a Big Daddy and the latter will clear the entire map. After the Rosie's down, resume fighting other Splicers.
 * If trying to capture the Little Sister, have a group distract the Rosie while one or two players go for the girl.
 * Use cover whenever possible, and try to move in a pattern which will confuse the Rosie. Movement-enhancing Plasmids such as Aero Dash and Geyser Trap will also help in doing this.
 * The Nail Gun and the Grenade Launcher are the two best weapons against the Rosie, due to their high damage output. The explosion caused by a grenade is also capable of momentarily blinding the Rosie, allowing for approach or escape.
 * The Big Game Hunter Tonic will increase damage against Rosies.
 * In rare cases, melee-rushing the Rosie can potentially drain a great deal of its health. Be sure to use stunning Plasmids beforehand to postpone death.
 * A decent strategy for low-level players in Civil War or Turf War is to equip a Shotgun and Winter Blast. Use the Plasmid on the Rosie and circle around it, blasting them with the Shotgun and meleeing them until out of ammo. Although this can take down a Big Daddy reasonably quickly, the player's proximity to the enemy may leave them vulnerable to a Big Daddy Stomp, which an experienced Rosie will use readily.

Behind the Scenes

 * The Rosie takes its name from Rosie the Riveter, a WWII-era American cultural icon used to persuade women to take up jobs to assist in the American defense industries of World War II.
 * The design of the Rosie appears to have been based off that of the Stratosphere Flying Suit.
 * Unlike an actual diving suit from the era that BioShock took place in, the Rosie's helmet conceals both the head and neck regions of the diver. The bullet shape of the helmet could have been intended to prevent risks of decapitation or to equip the diver within against the fatal amount of compression of Rapture's below sea level elevation.
 * The Rivet Gun used by Subject Delta in BioShock 2 is distinctly different from the one used by Rosies; the difference in the design can be seen when playing as a Big Daddy in the Multiplayer. It also functions differently; by default, Delta's Rivet Gun has a clip of twelve (or eighteen, if upgraded) Rivets in a can on the side of the weapon, which must be detached and replaced when reloading. The Rosie's Rivet Gun, on the other hand, never needs to be reloaded and can fire indefinitely until it overheats.
 * In BioShock 2, the Rosie's Rivet Gun has the same firing sound as Subject Delta's equivalent weapon. In the multiplayer, however, the Rivet Gun has the same sound as in the original game.
 * In the Proving Grounds, the Rosie and the Leadhead Splicer it's fighting are neither alive nor physically tangible: The Rosie's portholes are not lit up and any shot fired at them will pass right through.