Not much is known about the history of Krosakis. Krosakis has a spaceship with many modifications that suit his purposes including stasis fields that allow him to continue to feed off of the life forms he collects. He also has a crew of other beings of various races, which remain in his service for fear of ending up his next meal. When Gladiator sought to bring the Uni-Power back to the Shi'ar Throneworld to determine the cause of its power loss, both he and the Uni-Power were brought aboard Krosakis' ship by a tractor beam. This knocked out Gladiator for a short enough period for Krosakis' men to put Gladiator in one of his stasis fields. When Krosakis went to see gladiator he found the Uni-Power also on his ship (who could not get through the stasis field to bond with Gladiator), grabbed the Uni-Power out of the air and forcibly bonded with it by consuming its power giving Krosakis all of the cosmic powers of Captain Universe.
The power emitted by Krosakis, and the tainted nature of his acquiring it was detected by the Silver Surfer who was nearby at the time. Silver Surfer, who is one with the Power Cosmic, sensed the disturbance and rushed to meet Krosakis. Now also wielding great power, Krosakis was a match for the Surfer in raw power but did not have the proper experience in wielding it. When the it looked like he would lose, Krosakis grabbed the Surfer by the arms and began feeding on the Surfer himself. The Silver Surfer amplified the power Krosakis was draining, force-feeding him more cosmic energy than he could handle. This overload weakened Krosakis enough for the Uni-Power to escape his body. The Uni-Power then bonded with the Silver Surfer who brought Krosakis back to his own ship to be detained. With Krosakis captured the crew admitted that they remained in his service out of fear alone and were let be. Krosakis was taken into Shi'ar custody by Gladiator, who could deliver him to authorities who could properly handle and contain him. Krosakis is believed to be still in Shi'ar custody.
Krosakis has the ability to siphon the power and life energy of other beings through physical contact. He appears to also have technology at his disposal which will facilitate stealing energy from those he keeps in stasis aboard his ship. When Krosakis bonded with the Uni-Power he also possessed all of the powers of Captain Universe including flight, blast power, enhanced strength, and limited invulnerability.