The Eldest embraced him because Triglav believed himself divine while still a mortal. After his Embrace, he earned mythological reverence among the regional tribes and acted as Yorak's second-in-command.
Triglav and his brood were sent as envoy to Constantinople to warn the Dracon about embracing Gesu due to the predictions made by the Eldest. When the Dracon refused to listen and Gesu had fallen into a deep Torpor, Triglav and the Dracon battled each other.
The Dracon believed that Triglav had cursed his fledgeling as a means of punishing him for disobeying his sire. When Dracon finally found his brother-in-blood, the Carpathians shook with the horrible battle that ensued. Terrible visions wracked the elders of the clan with the outpouring of power and hate as finally, the Dracon tore Triglav’s three heads from his body, destroying him.
Although the feud between the two methuselahs ended that night with the destruction of Triglav, their childer still waged a silent war within the ranks of the Tzimisce clan.
Clanbook: Tzimisce Revised, p. 17, 34, etc.