Gravemind (achievement)

Were you looking for the Halo 2 level, Gravemind (Level), or the Flood form?

Gravemind is an achievement in Halo 2 for Windows Vista, and Halo: The Master Chief Collection. In the PC game it is worth 30 Gamerscore and is unlocked by beating the level Gravemind on Normal, Heroic, or Legendary. In The Master Chief Collection it is only worth 10 Gamerscore, though it can also be unlocked on Easy.

In the PC game, it is represented by Cortana's head. In The Master Chief Collection it is represented by a screenshot of the Gravemind holding the Arbiter and the Master Chief captive.