When one's own soul burns its way out from their body.
Combustion is caused by the cracking or shattering of an individual's celestial core. This usually happens after sudden and intense strain on the core, such as when attemping to draw in too much Aura at once.
Combustion can occur in any Luminous animal of either Luminosity, though it is slightly more common with Solar Luminosities. This is due to the steady and consistent Aura output of the suns, compared to the relatively finnicky moon cycles.
Combustion manifests in several stages of increasing intensity, eventually leading to death. The length of the stages depends on the severity of the broken core's damage, the size of the core, and the individual.
The individual can usually feel the precise moment when their core cracks. It's described as snapping or popping sensation somewhere within the chest, followed by pain. In rare cases, the initial crack is small enough that the individual does not notice until days later when the burning sensation starts.
If the core shatters instead of cracks, combustion happens almost instantly and kills the individual within the hour.
- Constant burning sensation in the chest, similar to heartburn; "slippery" control over Glow
- Burning sensation escalates; fever
- Moderate edylium leaking from the eyes; blazing pain in the chest; muscle spasms
- Excessive edylium leaking from the eyes, nose, and sometimes mouth; internal bleeding; delusions
- Non-stop edylium leaking from facial orifices and any open wounds; burns on the inside of mouth and throat (often eliminating the ability to speak vision loss; madness
- Burns on the surface of the skin that leak edylium; periodic uncontrollable blasts of Glow
- The core shatters, releasing a powerful Glowblast that turns the victim into a blackened husk and damages anything nearby
- Constant freezing burn in the chest; "slippery" control over Glow
- Sharp pain in the chest; chills; sluggishness
- Moderate edylium leaking from the eyes; escalated chest pain; numbness all over; uncontrollable shivering
- Excessive edylium leaking from the eyes, nose, and sometimes mouth; spasming and stiffness; delusions
- Non-stop edylium leaking from facial orifices and any open wounds; frostbite on the inside of the mouth and extremities; vision loss; madness
- Frostbitten skin; periodic uncontrollable blasts of Glow
- The core shatters, releasing a powerful Glowblast that turns the victim into a frozen statue and damages anything nearby
The only cure for combustion is to surgically remove the celestial core before the condition reaches dangerous stages. Since this requires access to very skilled surgeons and knowledge of the condition well before it becomes clearly recognizable, this solution is unfortunately not always an option. It is often better to relieve the individual of their suffering early than attempt to find someone that can help.
It is also theoretically possible to delay or even halt the advancement of combustion by using Celestial Negation. This could be done by exposing the individual to high amounts of their opposite Luminosity (either by being exposed to the related celestial body or through another Glowbeast), which negates the Aura inside of the afflicted and reduces its effects. If one were to do this consistently enough for long enough, they could possibly halt the progression of the condition.
Using Negation to prevent combustion is a precarious balance, however, and requires very careful monitoring. It has never been effective for longer than a few weeks, which isn't long enough to allow the core to heal. If the process could be maintained for long enough, it might be possible to completely stop the combustion.
Combustion will always end in death if the celestial core isn't removed, but how quickly that death comes depends on whether the core cracked or shattered. Most cases of combustion come from cracked cores, which result in a gradual progression of the condition over the course of a couple weeks to a month. If the core shatters, however, death occurs within 24 hours.
Lilthians and Humans
Both humans and lilthians can succumb to combustion if they are not careful. Dual-aligned lilthians are especially susceptable and almost guaranteed to combust. Lilthians aligned to Aza are also more likely to combust than those aligned to Sao.
Humans combust less often than lilthians do on average. Similar to dual-aligned lilthians, humans that are aligned to the light and dark sides of both moons are especially likely to combust. These people are exceptionally rare, however, and still aren't as likely to combust as dual-aligned lilthians.
Powerful and large dragons such as Savanna Plains Racers are known to cause significant amounts of damage when affected by combustion. Since they possess huge celestial cores, the shockwave of Stage 7 can be catastrophic.
The stages of combustion manifest slightly differently and progress much slower in dragons than they do in other Glowfauna. A combusting dragon may last as long as two months before finally succumbing.
Combustion can be prevented with caution and overall physical and mental health. It can also be avoided by limiting exposure to sources of Aura.
It is not wise to completely avoid using Glow in order to avoid combustion, as that may cause celestial atrophy, which actually weakens the core and makes combustion more likely. Regular exercise of the core is the best way to keep it strong and healthy.