Halo 2 Mission 12 Gravemind

Gravemind is the twelfth campaign level of Halo 2. The level takes place within High Charity, after the Gravemind teleports John-117 there. The Prophet of Truth has the Index, and the Master Chief must get to him before he leaves for the control room of Delta Halo. As the player travels through High Charity, they experience the beginning of the Great Schism. Strangely enough, apart from the opening cutscene, there is no contact with the Gravemind or the Flood. Also, the word "Gravemind" is not mentioned until two levels later in High Charity. This is the first level where Jiralhanae are fought, and is one of only four missions where there are no human weapons. This is the first level in which you can use the Brute Shot and the Brute Plasma Rifle.