295 Harken Watch
From Halopedia, the Halo wiki
295 Harken Watch was activated sometime prior to the end of the Forerunner-Flood war, and was present on Trove when the world was attacked by Flood forces. During the conflict, the shield world's surface was overrun and the monitor damaged. In response to this, 295 Harken Watch attempted to escape to the shield world's interior, with the retreat covered by three Prometheans - Animus-To-Remain, Habit-To-Sever and Malice-Begets-Demise. All three died to cover Harken Watch's escape, allowing the monitor to successfully seal off the shield world and prevent the Flood from gaining entry.
During the Human-Covenant War, Trove was obliterated in a short battle by human forces of UNSC Spirit of Fire. 295 Harken Watch was destroyed in this explosion, though fragments did survive. In 2557, a fragment of Harken Watch was recovered by the crew of the salvager ship Ace of Spades and partially-restored. The fragment, nicknamed "Little Bit", was adopted by the crew of Ace of Spades as the resident shipboard AI.
During the Halo Wars level Cleansing, an unidentified AI voice can be heard in the mission directing the efforts of the cleansing rings and Sentinels. It is unknown whether this voice represents the voice of 295 Harken Watch, or another sub-monitor or intelligence assigned to Trove.
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