From Halopedia, the Halo wiki
Ciar was present on Installation 07, where they had discovered a datastream at a Beacon that they identified as Forerunner. Ciar sent a datastream to both their colleague Dahk'rah and the House of Reckoning. He then continued to other Beacons to make more scans uncover more data.
Dahk'rah researched the datastream and analysed it, which helped Ciar with his research. After finding another datastream at a second Beacon, they reported this information to the scientists at Annex Ridge. With the help of Dahk'rah, they identified another Conduit. However, Ciar could not understand the transmissions and searched for further ways to understand their message.
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