Aureole

The Aureole, also known as the Shining Ring, is one of the Sept-Terrions and the treasure governing space. It was situated in the center of the floating city, Liber Ark, and is capable of granting the wishes of all its inhabitants through interaction with Gospels. During the Orbal Shutdown Phenomenon in S.1203, as part of the Gospel Plan, Ouroboros appropriated the Aureole. It is currently in the possession of Ouroboros' Grandmaster.

The Holy Beast sworn to protect the Aureole is Ragnard, the ancient dragon.

Background
As it name implies, the Aureole is a shining ring and predominantly gold. It was found in the top-most chamber of the Axis Pillar on the Liber Ark and served as its power source. Once the Aureole was removed, the Liber Ark could no longer sustain itself and fell into the Valleria Lake below.

Originally, the Aureole only passively granted wishes to owners of Gospels, orbment-like devices capable of interacting with the Aureole. Over the course of time and for reasons unknown, however, the Aureole gained autonomy and actively sought to assist humanity. Faction ruler Celeste von Auslese noticed this autonomy led to the deterioration of human lives. As described in a report found in Trails in the Sky SC, "the Aureole facilitated the creation of virtual realities intended to induce euphoria in participants. It even altered brain chemistry to achieve this. It was no different than taking a powerful euphoric stimulant and hallucinogen at the same time. Worse still, there were no side effects. No physical ones, at least."

The Sealing Mechanism
These observations led to the Sealing Mechanism, a plan devised by Celeste after having realised the Aureole's mode of operation had shifted from granting wishes to bestowing gifts. Since the Aureole is the treasure governing over space and holds absolute dominion over space itself, her goal was to sever its connection to both space and time. Having gained autonomy, it was not possible to simply wish for the Aureole to stop operating. Celeste concluded that another power source was required in order to stop the Aureole.

In her quest for an alternative power source, Celeste and her team resorted to the energy streaming through the septium veins and ordered to have facilities built on top of these veins. The Aureole, aware of Celeste's plan, prioritised the protection of the Liber Ark above else and considered her actions potential threat. To prevent the Aureole's elimination of the facilities, Celeste deceived the Aureole into perceiving the facilities as devices to monitor the activity of the septium veins. Ultimately, the facility, later known as the Sealed Area, was built roughly 500 arge beneath the surface where most septium veins gathered, on the eastern side of Valleria Lake and the present location of Grancel. In addition to the subterranean facility, the Ahnenburg and four Device Towers at the edges of Valleria Lake were built as additional measures for the Sealing Mechanism.

One of Celeste's team members was manipulated into revealing the plan to the Aureole, but since the knowledge of this particular member was limited to the underground facility, the Aureole targeted exclusively said facility through the manifestation of Reveries, self-defense mechanisms. While the majority could be held back by Celeste's team, one Reverie broke into the facility and reached the deepest sections. Moments before the Reverie could launch its attack, the First Barrier, the Temporal Freeze (, literally "Time Barrier"), was successfully activated. A light fired from the facility reflected off the inner wall of the Ahnenburg caught the Aureole floating in the sky, causing the Aureole to be sealed away and the Reveries to stop in its track. The one Reverie that broke into the facility is the same as the one that is being fought at the end of Trails in the Sky FC when the First Barrier is deactivated through the use of the Gospel.

The Second Barrier was activated using the four Device Towers spread through the land. The Second Barrier, known as the Gravity Barrier manifested gravity inside the dimension the Aureole was sealed in to make sure the Aureole was incapable of returning to reality in case the First Barrier were to fail. All Gospels that were remaining on the Liber Ark were sealed alongside the Aureole.