The crystals, called by the natives as "blightshards", are unstable, radioactive crystals formed after the complete glassing of the Eirfvenzienian homeworld hundreds of years ago, during the last periods of the Diyelir last stand against the Reaper onslaught. After a hundred years, these crystals formed entire mountainous regions along and below the equator of the planet. The crystals are highly contagious, and mutations often lead into gruesome deaths. However for some reasons, the people of that world slowly, albeit painfully, adapted into it, gaining their currently mutated forms.

And when the explosions happened, things got worse. Or horrifyingly better.

At the first hour upon the impact, toxic clouds of powderized blightshards, mixed with ash dusts from the triggered volcanic eruptions swept through the entire equator, unleashing a volley of mutations upon the panicking citizens. The crystals, unstable as it can be, proliferates like fungal spores, attaching into the ground and keeps on growing until it consumed a whole landmass for a relatively short period of time. A day after the equatorial explosions, a massive domino effect happened, with the blightshards rampaging across the whole world. The Diyelirs, while adept at environmental engineering, can't directly solve the problem as they're dealing not with organic matter, but with crystal overgrowths; the only thing that can be done is to stop it is to once again bombard the planet. But even that won't efficiently work. Even the Diyelirs themselves has to be taken out of the planet along with the Eteruans as the crystals can still pose a threat to them, even in their strongest state. Meanwhile, millions of Eteruans are dying on the planet, barely saved by the most advance medical advancements of their Diyelir kin. But the Diyelirs noticed something  great amidst the catastrophe.

Something more like a miracle.

The Eirfvenzienian's Ascendancy Genes, while helping them adapt to the current situation of their homeworld, is not fully activated yet. And they understand the reason why. In the earliest days of the Novashadow symbiosis integration, the adaptation level for the Diyelirs were slow yet constant, as they need to adapt every now and then to a certain dangerous trait or mutagen before they can be fully be empowered by it. As the Eirfvenzienians and the other natives are not fully exposed to those radioactive materials, they only received partial activation of the genes. But now, since the effect has been globally widespread.

A week after a war...

IRMIGADEON VALLEY FORTRESS

"My leader! Subject M4532 has been showing signs of stability upon exposure. The crystals are getting fully integrated in their cells, and their bio-blueprints are accepting the foreign crystals as part of their body systems. Mutations are now getting fully stabilized, and the subject's healthiest form was drastically changed to include a high resistance to radioactivity and flame, a hardened natural exo-skeleton made from the crystals itself, and high regeneration rate when exposed to the blightshards." one of the senior scientists said. "Good, progress then." Scheleina said, overseeing the project to help the natives.|

"What does it mean?" Lyrniux said, overhearing the situation. "It means that you're evolving. Congratulations, Marshall. You're now entering a new age, full of possibilities you never dreamed about!" Scheleina optimistically responded.

Spoiler: Brand New Age (hover to show)

Here ya go maaaate! I'm gonna have some flame-themed dudes soon, and you'll be part of their adventures.