After Delta is successfully made into a Big Daddy Andrew Ryan has them mass produced so that more little sisters are safe. A project is created with secret goals to the public and is only known as Fatherhood, but is a falure untill Group 6. Group 6 is in action for a long time before Andrew Ryan has them put into slumber pods. Only when Ryan needs them again will the Big Daddies of Group 6 be awoken, unfortunately the part of Rapture that the pods were in collapsed, crushing a large amount of sea slungs on the way down. The combined amount of raw atom opened a portal that swallowed up the part of Rapture and sent it to a different dimension, along with alot of splicers.