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Unlike Terran Dominion ghosts, they are not subject to controls such as neural inhibitors, but are expected to act with integrity. They can read and influence minds, even using their abilities to appear as other people through the use of psiweaves.
Shadowguards appeared to wear armor similar to that of the ghost hostile environment suit, with varying helmet design. Shadowguards were assigned both for covert operations and defensive duties, such as guarding the Umojan Protectorate space platform the Keep. Even among Terran Dominion ghosts, confronting a shadowguard was considered to be rare, and surviving such an encounter was unheard of.