Kelli Forston was originally a modern day treasure-hunter. However in her travels Kelli happened upon the Coralax, a race of merpeople that live in the underwater gratos of Sharkhead Isle and worshiped a primordial aquatic titan named Leviathan. The Coralax recruit for their cult by infecting ordinary people with living coral grown and controlled by their priests known as the Shapers. Once infected by the coral people are transformed into merfolk and brainwashed psychically by the Shapers. Kelli was transformed physically but not mentally and escaped before her mind was taken over. The details of Kelli's experiences with the Coralax are sketchy at best but when she awoke she was in an Arachnos facility being studied. Captain Mako had spied her and brought her in, though Mako has never confirmed if he saved her himself or just found her floating somewhere after some unknown escape method on her part but whatever Mako's part in Kelli's escape his goals have been far from benevolent. Mako had long since heard rumors of the merfolk living beneath the waves guarding a slumbering sea-titan and holding the key to it's powers and had been hunting them down to take the Leviathan's power for himself. Kelli Forston was Mako's hottest lead to the Coralax and their secrets.
Kelli has been with Captain Mako willingly ever since he brought her into Arachnos, for Kelli was as eager to discover her origins herself. The experience with the Coralax had left Kelli with no memory of her transformation and few memories of the larger details of her life before running into them. Kelli's best link to her past is Mako who has never confirmed or denied his leads on the Coralax and largely lead her on in order to exploit her powers. Captain Mako has dubbed Kelli “Barracuda” and established her as his right-hand henchman. Barracuda may or may not know she is being used but with no other leads Captain Mako is her best hope for making sense of the mysterious Coralax.