The Origin of the Big Daddy
The Big Daddy was an idea brought to Andrew Ryan by Dr. Yi Suchong. He knew that the Little Sisters would not survive gathering ADAM in Rapture alone, so he proposed that he create a group of protectors to patrol the city with the Sisters on their hunt for the precious resource. Ryan approved.
Although they may appear mechanical, every Big Daddy started as a human being. It's unclear whether the humans being converted had volunteered or were forced to. Dr. Suchong expressed his worry that they would have trouble finding suitable "candidates", though Ryan assured him that there would be no problem.
The steps taken to create one of these walking behemoths are quite gruesome. First, the bodies of each candidate are grafted into monstrous diving suits. Next, the subjects undergo voice-box modulation. This most likely enables them to emit the gutteral whale-like cry that can be heard echoing through the halls of Rapture as they roam, scouting for Sisters. Each subject is also injected with special pheromones that attract Little Sisters.
Finally, the subjects are given plasmids that enhance their strength and agility. These plasmids also cause them to become void of emotion and free-will and incapable of any thoughts outside of their one and only order: protect the Little Sisters at all costs.
The original Big Daddy prototype, referred to as "Subject Delta", was a little smaller, but more maneuverable, than the average Big Daddy. It was also capable of using both heavy weaponry, such as the drill or the rivet gun, and offensive plasmids, such as Incinerate! and Electro Bolt, simultaneously. For unknown reasons, Delta was never activated and put into use,and was instead kept in hibernation for the majority of its existence. In addition, Subject Delta was the first Big Daddy to be successfully bonded to a Little Sister. Subject Delta is the player character and protagonist of BioShock 2, having finally been awakened ten years after the events of the original BioShock. It appears that Subject Delta possesses free will, unlike the other Big Daddies, though the implications of this have yet to be fully explored.
Mr. Bubbles, Mr. Bubbles, are you there?
Whenever the player sees a Big Daddy, there is almost always a Little Sister somewhere nearby.
The Big Daddies roam the halls of Rapture looking for bodies that a Little Sister can harvest. When the need for a Little Sister arises, the Big Daddy will find the nearest vent - which the Sisters use as a means of safe transportation throughout Rapture - and bang on it. This will alert nearby Sisters to his presence, letting them know it is safe to come out. The Sister will then crawl out of the vent, walk with the Big Daddy to his find, harvest it, and proceed back to the safety of the vent system.
Interactions with the Player
Big Daddies are normally passive toward the player, but if you get too close they will push you away. They will only attack in retaliation for you, or another enemy, attacking them or their Little Sister cohort.
You may notice that the lights on the dive helmets of the Big Daddy change color depending on their mood or hostility:
- Yellow - The Big Daddy is in passive mode, and will not attack unless provoked.
- Red -The Big Daddy is aggressive, and is either attacking you or another enemy.
- Green - The Big Daddy is hypnotized by the player, and is acting as if the player is a Little Sister.
There are four different types of Big Daddies:
- Rosie - Equipped with a rivet gun and the ability to throw proximity mines, should they choose to do so. They can also charge the player and hit them in melee.
- Bouncer - Equipped with a large drill on their hand, the Bouncer can only attack in melee - though they deal significant damage. They can also charge the player.
- Elite Rosie - A "buffed up" version of the Rosie, they are encountered later in the game. They are more aggressive and deal more damage.
- Elite Bouncer - Like the Elite Rosie, they are a "buffed up" version of the Bouncer encountered later in the game. They are more aggressive and deal more damage.
When the player defeats the Big Daddy guarding a Little Sister, he may choose whether to save the Sister for a small amount of ADAM or harvest her for a larger amount.