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Following Ghaul's coup, Tha'uul continued to serve as a statesman in the Cabal's government, and was aware of the Red Legion's plans to invade the Sol System to capture the Traveler from humanity. As he walked through the streets of the Cabal's capital, Tha'uul realized he was being followed by a being made of Arc energy. Panicking, he fled through the streets, eventually turning into a dead end alleyway. He relaxed, believing he had escaped his pursuer, whom Tha'uul believed was a Stormbringer Guardian, unaware that The Fulminator was hovering above him. The Fulminator assaulted Tha'uul and tortured him, learning of the Red Legion's plans to invade the Sol system and other information on Cabal troop movements. Once the interrogation was finished, Tha'uul was killed by Calus' agent and his charred husk was left in the alleyway.
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