Fluorinated Perikin

Through inexplicable transmutation rituals and alchemical processes, you have taught your body how to digest fluorite and combine it with salt to produce an entirely new pyrophoric compound. This compound, known as chlorine trifluoride, replaces what you would normally use to power your breath weapons.

Ability Score Increase. Increase your Constitution score by 1, to a maximum of 20.

Chlorine Trifluoride. Your breath weapons now ignore fire resistance from all creature types. Your breath weapon also ignores fire immunity except if an affected creature is incorporeal, an Elemental, or a Construct, in which case they treat the fire immunity as resistance. Additionally, creatures who are damaged by your breath weapons cannot regain hit points by any means until the end of your next turn. Finally, your breath weapons destroy all mundane, nonmagical objects within their area of effect over the course of one turn; objects which do not fit within the breath weapon's area of effect have the affected portion of it melted away.