From Halopedia, the Halo wiki
Mrata was among those who accompanied Rojka 'Kassan to stop Melody Azikiwe from unfreezing Gray Team from their cryo chambers. Upon entering the hangar Gray Team was in, Mrata was attacked from behind by Adriana-111. Adriana opened fire and charged at him, knocking his Type-1 energy sword from his hand. Adriana got the upper hand and repeatedly fired her Type-25 plasma pistol point-blank up into Mrata's chin until he stopped moving.
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