Play>Through-(Xbox MCC) Halo 2: Part 10 /Gravemind.

The Gravemind ( Inferi sententia, meaning "Thinking Dead"), is the final stage in the life cycle of the Flood and is the ultimate hivemind of the Flood. It is a near-omniscient creature with complete control over all Flood forms. A particular Gravemind is the secondary antagonist in Halo 2, and a main antagonist in Halo 3.