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Praetorians have reinforced Void shields and always use the standard Minotaur weapon, the Torch Hammer. Their primary purpose appears to be to defend and reset Sync Plates from non-Vex forces, as Sync Plates activate numerous pieces of Vex technology. Upon capturing the three Sync Plates to construct the Spire that unseals the Vault's main entrance, Praetorians will spawn relentlessly to stop the Spire's completion. More are encountered while facing the Gatekeeper, and will again attempt to reset nearby Sync Plates.
List of appearances