From Halopedia, the Halo wiki
After most, if not all, males left the Nes'alun keep during the Blooding Years, Elar was left to care for the children and other females of the keep. Shortly after the male's departure, the keep was attacked by Lacalu keep, which hoped to gain more Acroli land. Elar defended the other females and children in a small farmhouse for an unknown length of time. Evan Phillips was then teleported nearby, and, because of his apparent link to the Forerunner technology that teleported him, was allowed inside by Elar. She asked Shobar to hand over a plasma pistol to arm Phillips, and they then defend the keep from a wave of attackers. After the skirmish, Elar 'Nas called Avu Med 'Telcam to inform him that the human the Abiding Truth wanted found was with them. Soon afterwards Kilo-Five, who'd been searching for Phillips since he disappeared, arrived to retrieve Phillips. Much to the dismay of Phillips, Elar and the other Sangheili were left to fend for themselves once Kilo-Five departed.  Elar and the others of Nes'alun keep were killed by the invaders soon after.
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