Years after the End War, the Nerazim developed a new psionic weapon: a warp disk that emitted psionic energy from its edges, creating a powerful ranged weapon. Recognizing the potential such a weapon could have when combined with telekinesis, Hierarch Artanis and the Nerazim sent Ulavu to Korhal IV to locate a terran ghost with such an ability, as well as ascertain the threat terrans posed to the future of the Daelaam. Ulavu was to procure the aid of the ghosts in further developing the weapon, his mission kept secret from the terrans due to Artanis not yet fully trusting Valerian Mengsk. Ulavu was picked up on a battlefield by the Terran Dominion, and was taken to the Ghost Academy on Ursa.
While he was taken care of during his time at the Dominion, Ulavu refused to state his purpose or why he was "exiled," and Hierarch Artanis refused to take him back. He gave valuable insight on the protoss and zerg to the Dominion, and proved a valuable asset. While at the academy, he met many ghosts but deemed the two with telekinesis that he met, Mai and Glistrup, were of unsuitable character to aid his research. He instead befriended Tanya Caulfield, a ghost with the power of pyrokinesis. However, as they grew in friendship, he decided against using her to help his weapon research, and instead opted to find another suitable candidate. This decision caused a rift between him and Hierarch Artanis, causing him effectively to be exiled.
When the Ghost Academy was moved to Augustgrad, he and Caulfield were moved with it. While there, Ulavu heard that a telekenetically powered terran psychic died on Chau Sara, and he guessed that the power may be transmitted through the genetic line. He also heard of a gathering of Chau Sara survivors meeting at a bar called Dante's Circle, and so Ulavu escaped the facility and attempted to communicate with the bar patrons. This was met poorly, as many still held animosity toward the protoss due to the glassing of Chau Sara. One man named Rylan attempted to pick a fight with Ulavu, but Tanya, who noticed he was missing, intervened, using her pyrokinesis to stun the man and allow the two to escape.
When the Dominion traveled to Gystt, Ulavu accompanied them on Valerian's request, and joined a small survey team sent to the planet to investigate the motives of Overqueen Zagara. After they were cornered by renegade zerg under the control of the chitha, Ulavu's Nerazim nature and true mission were eventually revealed to the group, hurting Tanya with his secrecy. They eventually reconciled, however, and agreed to continue their friendship should both survive the planet.
After being tricked into destroying a nest of adostra, creatures made from xel'naga essence to germinate life, Ulavu and his group sought to unravel the plot of the strange chitha broods. They eventually moved to the final gathering of the creatures, defeating the chitha and the zerg they controlled and holding the point long enough for Zagara to arrive. They pieced together that it was Abathur who had planned the attacks in order to destroy the adostra, and that he's be aboard the levithian used by the queen Mukav.
Aboard Zagara's leviathan, Ulavu killed Mukav, but was mentally attacked by the powers of Abathur's chitha, Abathur was surprised by the presence of a protoss warrior and brought the chitha's full power against him. In the aftermath of the battle Ulavu was badly wounded but survived, and was later ordered back into the Daelaam, as Artanis worried the exposure of his true mission would cause problems between the two races. However, he vowed to keep Tanya as a close friend.
While he was a researcher, Ulavu still carries weapons on his person. He utilizes collapsible warp blade emitters that are able to come apart and flatten around his hands, allowing them to be discreetly carried and covered by gloves; when Ulavu needs to use them the emitters can re-assemble in moments. However, they are experimental and are neither as sturdy or powerful as normal warp blade emitters.
Ulavu also possesses another experimental weapon, a throwing disk incorporating warp blade technology. The disk is the size of a human drink coaster, and when thrown emits a field of warp energy around it approximately a meter in diameter. The disk's blade is capable of slicing through the same types of materials as warp blades, but deactivates upon hitting something it cannot penetrate.
Ulvau also implies that he is capable of 'light-bending', therefore would be able to cloak like a dark templar under normal circumstances. However, the effect on his psionic abilities by the chitha render him unable to make use of this.