Sentinel battery

Sentinel batteries are items used to power Night Sentinel machinery. They are used to unlock bonus items in the Fortress of Doom.

Sentinel battery locations

 * Exultia (1)
 * Cultist Base (3)
 * Doom Hunter Base (2)
 * Super Gore Nest (3)
 * ARC Complex (3)
 * Mars Core (3)
 * Taras Nabad (3)

In addition, extra batteries can be obtained by completing all challenges in a map.