Onyx United Research Project

The Onyx United Research Project was a joint Swords of Sanghelios-UEG research group attempting to uncover Forerunner technology on the shield world known as Trevelyan. Despite the alliance, tensions were still high between the two factions, aside from conducting research in the field the Sangheili rarely left the researcher's settlement, Paxopolis.

List of appearances

 * ''Halo: Fractures
 * Lessons Learned