OVERTURE
It was circuit after clinical circuit around the bird's eye - or in his case, a dragon's eye - perch above a cloud-suspended land mass that bordered on desolation. Only the bizarre rodents (chicken-like, the Earthens would suggest) touring the weed-invaded masonry through the sandy haze that skimmed the once-fertile ground, suggested any form of remaining life on the land pillaged by the Twili. The shadowy tribe was forced to accelerate their preparations for universal conquest in light of their Princess' defection to The Earth, and the understanding forged between herself and the Hylian, who seemed to carry an aura of messiah-like stability with him. But the remaining leader of the Twili had been waiting his entire life to dismantle that false stability, which allowed the three realms to live in relative harmony with each other in their respective senses of solitude. Deciding once and for all that its so-called sister realms required a long-overdue history lesson in the fate of its cosmic shoehorning into suppression, the leader appealed to divinity for assistance in sturdying his army for the processes of an uprising. Ignored by a Pantheon that valued plain existence above all else, his prayer was promptly claimed by the most militaristic and destructively mischievous demigod possible, a figure who had the power to be recognized as a full-blown god, but was barely kept at bay with his deadly ambitions by the deities of the Grand Universe, who strove to ensure the existence of its trio of realms. Their efforts to pair a sense of peace with that existence remained successful, in keeping with the fragile incarceration of their malevolent offshoot, until the leader of the Twili decided to disturb that peace. An appeal to the false god was all that was necessary to free him from the chains of his superiors and leave him free to use his god-mocking powers in whatever way he saw fit. And he saw it fit to invoke a pre-peace universe that was buried so deep within its history, that it failed to even survive the lore and legends that enriched the realms, especially lore-driven Hyrule, for countless generations. In the Land Of Twilight however, that memory was as fresh and intact as it was in the early stages of the universe's existence, because it was the truth. A truth that was relayed to successive generations with a sense of conviction that does not accompany mere storytelling.
For the dragon appointed sentinel of the City In The Sky, truth, purpose, and instruction all came together under one meaning, which in turn defined all that was left in the brain of the sentinel, save the necessary instinctive functions of flight and flaming exhalation. Like the memory in the hard drive of an Earthen's computer, his own was lost in some kind of viral spell at the hands of the Twilight Prince amid the cataclysmic swarm of The Change. All knowledge of his past and present, including the awareness of his very identity, was obliterated by the Prince, rendering him more a program than a dragon. With no trace of a conscience, he dutifully, automatically, carried out the orders left to him following the satisfied departure of the Twili: fly a perpetually circular path around the boundaries of the "City" in the unlikely event of the pair - the Hylian in particular - emerging from the depths of The Earth still alive, arriving too late to issue a warning of the imminent insurgence to its pre-cursed citizens. Upon arrival, they would inevitably scour the land in search of clues as to what happened to this place while they were diverted by a troop of Twilit soldiers, dispatched to study The Earth in a shadow of secrecy (something that came natural to the Twili) for weaknesses that could be exploited in the midst of their invasion, the final rung in the Twilight Realm's uprising. This should afford the sentinel plenty of time to dispose of the Hylian. He and his rogue partner may somehow survive the obstruction laid out by Twilit foot soldiers, but there was no hope of dodging a Twilit dragon.
This was not only a generic dragon that would confront them - an insurmountable task in itself - but one who will have circled the grounds to the degree of sporting an instinctively photographic memory of all its nooks and crannies.