Overview
Alrest is a world set upon a sea of clouds, stretching from one horizon to the other in a featureless expanse. Rather than the landmasses many consider to be the norm, the lifeforms of this world have built their societies upon the bodies of the massive creatures known as Titans. These Titans have wandered the Cloud Sea for as long as anyone can remember, each having it's own particular course and range around the central fixture of this world -- the great World Tree, atop which is said to be the ancient promised land of Elysium and the creator of all life, The Architect.
As the legend goes, all beings used to live alongside their divine creator within a golden paradise they called Elysium, where anything the heart could desire was provided and life was simple and good. One day, mortals somehow angered their creator and were cast out of Elysium to live at the base of the Tree. Survival was difficult and hope seemed lost as population plummeted and extinction seemed imminent. Just when it seemed all was lost, The Architect took pity on them and sent below his final gift for his wayward children -- the Titans.
It was upon these mighty creatures that the survivors would construct homes, societies, and eventually great nations as the population recovered and then increased. Scientific advancements were made, leaving behind their primitive beginnings and advancing toward something akin to a steampunk fantasy level. Steam rifles, dirigibles, clockwork flying machines, factories, and various gadgets and devices are all commonplace in the present.
Greatest of all advancements are the Blades. No one can recall from where the Blades originated or what their intended purpose was, but most agree that life as it is currently known would be extraordinarily difficult without the assistance of these indispensable companions and peerless warriors. They, and their bonded partners known as Drivers, are an omnipresent sight no matter where one might travel in Alrest, with many nations' power and prestige being measured by the number of Drivers within their ranks.
Even the might of Driver and Blade cannot stop the current crisis facing the people of Alrest. For reasons unknown, the Titans are dying out. It was a process which seemed to begin with the terrible Aegis War some 500 years in the past, during which two Blades of terrible power fought a battle with all of civilization at stake. The protector of mortals, a being known as the Aegis, managed to defeat the great destroyer at a terrible cost -- three entire Titans, along with the nations and populaces living upon them, were slain and sent to the lifeless depths of the Cloud Sea before peace was won.
Since then, there have been fewer and fewer Titans roaming the sea, the ever-dwindling living spaces of Alrest sinking along with their depleted corpses. No one understands why this is happening, but there is one thing perfectly clear to the leaders of the remaining nations -- there is nothing more precious than land and no price to steep to pay to secure survival for their people. Armies are quietly bolstered and equipped, tensions high as each nation eyes covetously the lands of their neighbors and allies, knowing that the death of their own home and the extinction of their people can come without warning unless they are prepared to do what must be done to secure their future.
Core Crystals
The essence of a Blade's life and a valuable treasure to the people of Alrest. By focusing their will and desires upon an unbound Core Crystal, it is possible for the possessor to bring into existence the beings known as Blades. Blades are sentient life which take on a form very much influenced by the heart and will of their Driver, most often humanoid in nature.
Summoned Blades are bound to those calling them forth from the crystal, beings henceforth known as Drivers. Blades gift great power upon their Driver, who in return provide energy to their Blades in a sort of symbiotic relationship which is quite beneficial to both parties, elevating them to the peak of Alrest's armed forces and mercenaries.
While a Blade is functionally immortal, immune to the ravages of time and rapidly healing from any injury, they are not eternal -- their existence is bound to that of their Driver. When their mortal Driver inevitably dies, be it due to natural causes or untimely incident, a Blade returns to their Core Crystal as if they never were.
While a Core Crystal can be used again at a later time and the residing Blade called forth once more, the emerging Blade is resurrected in form alone -- all memories of their past existences are lost and only the most basic foundations of their personalities remain upon their return to life, their future to be shaped by their newest Driver. This can be very disconcerting for most natural residents of Alrest and discomforting enough that even those who knew a Blade's prior incarnation for their entire lives can find it extremely difficult to remain in their presence for long.