Ebaria Epic Boon: Fire Walker

You have immunity to fire damage. And if you would be dealt fire damage by a hostile creature, you may choose to instead convert the energy into your own power. The next time you would deal fire damage within a minute, it does 20 more (cannot stack). You can also cast 9th level fireball and 9th level fire shield (save DC 20, or yours, whichever is higher) at will, without using a spell slot or any components. This spell cannot be countered, and works in antimagic areas. You are unaffected by extreme heat conditions. While you have the fire shield spell active, ice turns to water within 10ft of you.

Additionally, once per round of combat on your turn, when you deal fire damage with a casting of a spell or an attack roll, you gain a charge of Firepower, which increases your movement speed by 10 ft and gives you a bonus of 1 to your armor class. The charge of Firepower remains until the end of your next turn, unless you gain another one before it disappears. Once you gain 4 charges of Firepower, you lose them all and all bonuses they grant to you, instead gaining an additional action on your current turn, which you can only use to make a single attack, cast a cantrip or take a dash/dodge/disengage action.