Prior to the events of Planet Hulk, Elloe Kaifi was the daughter of Ronan Kaia, a member of a high-ranking family on the planet Sakaar. Enjoying a relatively carefree life for most of her early years, Elloe's life changed when her father spoke out against the Red King, resulting in his titles being stripped from him and he, his daughter and her bodyguard Lavin Skee being sent to the gladiator training school, the Maw. When her father protested at his treatment, he was killed by the guards shortly before the training battle began, of which Elloe and Lavin were two of the seven survivors. Initially lacking combat skills, Elloe received training from Skee before she left the group to try and aid rebels in an attack on the emperor.
After she and her fellow rebels were captured and brought before her former comrades in the arena, shortly after their third victory in the arena over the 'Silver Savage', the gladiators were ordered to kill Elloe and the others to earn their freedom. Hiroim the Shamed revealed that Lavin Skee had been killed in battle earlier, and that the others had formed a Warbound Pact; thus, since Skee had served Elloe, the Warbound could not kill her without violating their oath. Although their obedience discs were activated, the Warbound were freed when the Surfer destroyed the discs, allowing them to escape and begin a rebellion against the Red King.
Although the physically weakest member of the Warbound—particularly after Miek's evolution—Elloe remained one of the members most dedicated to the death of the Red King. However, she retained her old family loyalties; after the Red King was killed in a fight with the Hulk and her mother was discovered to be one of the King's remaining supporters, Elloe fought against fellow Warbound Miek in the arena before the Hulk told both of them to cease.
Following the destruction of Sakaar, Elloe travelled to Earth with the remaining members of the Warbound to seek revenge on the Illuminati who exiled him. Accompanied by Hiroim, she fought Iron Fist, Echo and Ronin when seeking to capture Doctor Strange, although the two were defeated by the Sorcerer Supreme before he went on to confront the Hulk.
In World War Hulk's "Aftersmash" 1 Shot followup, Elloe is heavily wounded impaled on a spear to end hostilities between Sakaarians and Hivelings, when the Sakaarians began to kill Hivelings in retaliation for Miek's complicity in the destruction of Sakaar. It is also revealed that though she was not part of Miek's betrayal, she had harbored a shameful secret in that part of her was glad when Crown City was destroyed, because it gave her an excuse to give in to her anger and hatred.
She is shown alive, but gravely injured with the remaining Warbound when they are transported to Gammaworld, a massive energy dome placed over the Southwestern United states by The Leader.