Hataaru lived in Mac'Aree on the eredar homeworld of Argus. An echo of him called Councilor Hataaru can still be found there, watching a jed'hin match at the Circle of Aspirants. Hataaru says he participated in a round or two of jed'hin in his life, but the competitors are far better than he could ever hope to be and he must admit he is envious.
Following the ejection of the darkened K'ara from the Genedar Prophet Velen found himself able to see the Void's desired futures. Finding it difficult to distinguish visions of true calamity from glimpses into the Void's dreams of a corrupted universe convinced Velen that it would be disastrous if he were the only leader among his people. Thus the exarchs (a council of sages that would oversee different aspects of draenei culture), was created and Hataaru was chosen to be exarch of the Artificers, tasked with building armor, weapons, and settlements. Among Hataaru's first creations were arkonite crystals, which served as conduits of arcane energy which brought light and power to draenei society and also allowed them to build constructs to protect their homes from danger.
When the Burning Legion manipulated the orcs into attacking the draenei Hataaru initially thought the orcs were victims of the world's natural disasters and elemental upheaval and merely sought to defend their holdings. Upon discovering the Burning Legion had been manipulating the orcs Hataaru and his fellow leaders knew they could no longer defend their holdings and ordered their forces to withdraw to Shattrath and the Temple of Karabor.
The draenei helped prepared the defense of the Temple of Karabor and against all odds the outnumbered draenei were able to push the relentless orcs back. In response Gul'dan and the Shadow Council used the Dark Star to break the stalemate. Though Hataaru and many of the draenei survived, they were forced to abandon the temple to the Horde. Knowing that Shattrath was doomed to fall Hataaru, along with his fellow exarchs, argued against Velen's decision to be among the defenders of the city. Convinced that the best hope for their race's survival was under Velen's leadership, the exarchs persuaded Velen to leave Shattrath. Thus Velen would flee with the civilians while bulk of their military might would remain within the city, in order to sacrifice themselves to ensure the survival of the draenei race and trick that orcs into thinking that they had slaughtered all of them.
Hataaru's fate is unknown but he was presumably killed by the Horde.
It's possible that like his alternate universe self he was killed by Exarch Othaar. The Orcish Horde's attack on Shattrath would have provided him with the cover to do the deed.
- Patch 7.3.0 (2017-08-29): Added.