Needler Sentinel
From Halopedia, the Halo wiki
The Needler Sentinel is a glitched Forerunner Sentinel that can be found on the Halo 2 Campaign Level Quarantine Zone. It is a lone Sentinel Major that shoots Needler rounds rather than the conventional Sentinel Beam and when destroyed, drops a Needler.
The Needler Sentinel can be found on the leftmost side of the first glowing orange indoor area within the ruins of the Sentinel Constructor Factory.
Trivia
- Bungie originally planned to equip certain Sentinels with different weapons but the idea was scrapped. This Sentinel was simply missed during the deletion process[1].
Sources