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Murok 'Vadam was born in the state of Vadam to the noble House of 'Vadam on Sanghelios, the homeworld of the Sangheili. He resided in Vadam keep, alongside Arbiter Thel 'Vadam, the leader of the Swords of Sanghelios and kaidon of Vadam.
In October 2558, Arbiter Thel 'Vadam and his Swords of Sanghelios secretly convened within the Elder Council Chamber in the Nuusra territory to prepare for their final efforts to rid Sanghelios of Jul 'Mdama's Covenant. Desperately needed an advantage over the Swords of Sanghelios, the Covenant promised 'Vadam power and prestige in exchange for the location of where the Arbiter and his soldiers were meeting, to give the Covenant an opportunity to assassinate the Arbiter. Failing to recognize that the severely weakened state of the Covenant could do little to give him what they promised, 'Vadam informed the Covenant that the Arbiter and his soldiers were at Nuursa's Elder Council Chamber. However, 'Vadam's attempted betrayal failed in the resulting Battle of Nuusra when Spartan-IVs of Fireteam Osiris came to the aid of the Arbiter at the chamber and they were extracted back to the Swords of Sanghelios' encampment elsewhere in Nuusra.
Interrogating a Covenant Unggoy in an effort to learn how the Covenant had located the Arbiter at the Elder Council Chamber, Sword of Sanghelios security officer Mahlo 'Turagg learned that 'Vadam had betrayed them and 'Turagg promptly informed the Arbiter. When Thel confronted him, Murok made no attempt to hide his betrayal, believing that the Arbiter would not execute a member of his own clan. Murok was mistaken, as Thel proceeded to kill him. 'Turagg documented the event in his data pad and these notes were later accessed by members of Fireteam Osiris.
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