When the Romans had conquered Greece, some of the Titans had been forgotten—left behind to make room for others, overlooked in their worship as their domains were placed onto other gods. One of the most well-known examples of a domain being passed off is the case of Helios to Apollo; where Helios had once been the Sun Titan, charged to bring sunlight to the world with the sun chariot, the job was passed to Apollo, willingly, when the Romans slowly forgot the name of Helios.

Even so, Helios never truly faded as Pan had; mortals worshipped Helios as the sun, even if it was fleeting and barely enough—it kept Helios alive and well despite his role having been taken up by Apollo. He lived a quiet life amongst mankind, hidden within them, never attempting to reclaim power and simply enjoying the simple task of being alive after eons of having served.

Titan blood was never supposed to mix with mortal blood, though—not after the First Titan War.

Despite this, Guest strolled into Camp Half-Blood after being chased by a massive, vicious drakon with scales that glittered like molten gold beneath the summer heat. It took half of the Ares cabin, a scattering of Apollo kids, and Guest to drive the beast off; however, the final blow had come in the form of a flare that nearly blinded everyone present, straight from the hands of the newcomer.

Helios claimed Guest—a flare of an emblem of Helios that had been all but forgotten with time—immediately before anyone could mistake the power for one of Apollo's many children. Of course, Guest knew their father; Helios raised them with their mother, after all, and he spoke of stories regarding gods, Titans, monsters, and histories that were more accurate than anything found in textbooks. For everyone else, though, it had been quite the shock.

That evening, as the sun set on the camp, Apollo appeared, having called in a favor from Artemis to drive the sun chariot to have the time to appear to greet this anomaly half-blood. Sunlight flared through the camp with his arrival, soothing into the usual light levels to reveal his golden hair and infuriatingly easy smile.

"Well, well," Apollo drawled with his usual arrogance, stepping through the camp as though he owned it (gaining a grumbling from Dionysus, who promptly retreated to the Big House to not deal with his half-brother). He stopped not before any of his confused, waiting children but Guest. "You are an interesting little thing, aren't you? A spawn of old Helios."