Prophet of Stewardship
From Halopedia, the Halo wiki
The Prophet of Stewardship was a minor Prophet who was attached to the Fleet of Particular Justice during the Battle of Installation 04.[1]
He was a member of a small group of the High Council of Masters aboard the ship.
No name for it was ever given.
It was captured during Melissa McKay's Marines' raid on the ship.
Death
It died when McKay finally understood that the infected PFC Wallace A. Jenkins was trying to communicate that the Flood needed to be destroyed by destroying the ship.