Rtas 'Vadum
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Rtas 'Vadum, or Rtas 'Vadumee, was an Elite Ship Master for the Covenant. He is the Ship Master on the Shadow of Intent and the Fleet Master of the Fleet of Retribution. 'Vadam was a key element during the battle of Installation 05 and the Human-Elite alliance. While serving with the Covenant, he was commanded to hunt down Sesa 'Refumee, the leader of the heretics.
While the battle of Earth raged between Flood, UNSC, and Covenant separatists, Rtas 'Vadum aided Lord Hood and traveled through the portal to The Ark. He lent his troops to the UNSC to help defeat the High Prophet of Truth. After Truth's death, 'Vadum and Thel 'Vadam (The Arbiter) helped the Master Chief defeat the Gravemind and rescue Cortana aboard High Charity. After the end of the conflict, both 'Vadum and 'Vadam travel back to their homeworld, Sanghelios.