From Destinypedia, the Destiny wiki
The Seraphs, also known as the Seven Seraphs, were a peacekeeping force that was active during the Golden Age. They worked closely with the Warmind Rasputin with each member being entrusted with a Warmind Khanjali.
They operated from several combat bunkers across the system which were built and stored by Rasputin. Eventually, all of the Seraphs were wiped out during the Collapse. When the Guardians joined forces with Rasputin, they uncovered their armaments in defunct bunkers and rediscovered their legacies.
During the events of the Collapse, the Seraphs had been mobilizing by Rasputin when word reached them of events surrounding Titan, which had suffered a massive extinction-level event caused by the Pyramids when they manipulated the planet's gravity into unleashing massive tsunamis across the methane oceans and flooded their cities.
On Earth, First Lieutenant Artur Voronin and his superior Morozova were stockpiling munitions as surviving civilians were being escorted into a nearby evac station to wait out the ongoing calamity in cryo-induced hibernation. By then, the Pyramids had unleashed a paracasual storm across the surrounding landscape, separating Voronin and Morozova amidst the chaos and threatening the station and its people. Voronin attempts to save his mortally-wounded officer just as the Traveler came to the planet and into his vicinity. Artur and Morozuva were then saved by faculty from the nearby evac station and placed in cryo-sleep; the last thing that the first lieutenant had seen was of the Traveler's sacrifice.