alright here's the "official" firesoul version of Vent.

Vent occasionally turns firesoul in extremely emotional scenarios (with extended rest) or randomly some days. Vent was born airsoul but in their early years as a child they started to show signs of an extra manifestation. At first it would only be an arm or leg that would change manifestation but it could quickly spread to half of their body randomly. These sudden changes were very painful mentally as it caused Vent to deal with two personalities at once. Occasionally one would swallow up the other, not to be seen again for days or months. Over time Vent learned to somewhat control their manifestations, never allowing both at once and being able to control which element would manifest upon waking up. Though sometimes, under extreme stress, there is no decision.

Vent (pronounced Vhant)
race = genasi
class = swordmage
agender/genderfluid
pansexual
flaws = fierce, blunt, impatient, reckless
assets = confident, concerned
motivation = vengeance, desire
fear = of being controlled

airsoul Vent - https://www.weasyl.com/character/65220/vent