Most of them were merely messengers: they appeared, verified the identity of the message's recipient, gave commands, and left. The sentinels were created as part of the Contingency. Finally, sentinels had human-like five-fingered hands with a holoprojector built at the center of their palms, and a retractable needle that allowed them to verify the identity of a message's recipient by analyzing their blood. Their glass masks were in fact screens used to display lifelike images of the late Palpatine's face. Īlso unlike battle droids, sentinels had heads that resembled a helmet with a smooth glass dome. Others, however, had no such hand coverings. Over those robes, some of them wore red jackets that had gloves built in. However, contrary to those battle droids, sentinels were clothed in bright red robes that resembled those once worn by the Emperor's Royal Guard.
Sentinels were humanoid in shape, and their bodies greatly resembled the B1-series battle droids once used by the Trade Federation and the Confederacy of Independent Systems.
' All sentinels and messengers are programmed to serve will, even in death.' ―Gallius Rax's sentinel explaining his purpose to Rae Sloane
