Idk

RainbowDoggieUnicorn Goretober

2. Extra limbs/eyes/etc. - Surface of Evolix contains many eyes

9. Monster form - Stealth shell of Evolix appears as Xelflare's body

13. Decay(?) - Multiple fill lights to brighten the scene, with one bright light that is essentially burning Evolix

17. Backstabbed (literally or figuratively) - Evolix withstanding a sharp object

20. Parasite - Evolix themselves

27. Possession/corruption - Xelflare being possessed by Evolix via a full takeover

The yellow spots on Evolix's chest are the blisters formed from the purple UV hitting them. The lime spikes are a subtle reference to Bossmiller's mascot Boss.

What you're seeing here looks like Xelflare, but is rather the form and shape of him as a possession shell for his voidshade parasite Evolix.

Evolix is not omnipotent, but they can't be hurt from just normal means or killed entirely. In addition, the dialog above has Xelflare inside the internal state of their stealth shell while Evolix replaces his body with their mass.