Path of the Volcano Born

A Barbarian subclass that brings out the destructive power of magma

Brimstone Aura

While raging you become resistance to Fire and Frost damage

Brimstone

When this effect is activated, each hostile creature within 10 feet of you takes 1d4 damage at the start of each round.

 

increases to 1d6 at level 5, and 1d10 at level 8

Burning Blade

while raging your weapon deals deals extra fire damage equal to your level. (2 times a day you can ignore resistance to fire damage, dealing full damage to fire resistant creatures/enemies, you can decide this after the attack is made but before damage is rolled. This number increases to 5 times a day at level 15)

Billowing boon

At 10th level, while raging you become immune to fire damage, and all allies within 10 feet of you deal extra fire damage equal to your level

Breaker of earth

At level 14, as an action you call forth the powers of a volcano and split the ground in front of you. The earth splits open in a Jagged, Firey line 25 feet long, 10 feet wide and 10 feet deep. Any creature in the line takes 4d4  bludgeoning damage as they fall in, and 6d6 fire damage as flames lash out at the creatures (you can use this a number of times equal to 1/2 your proficiency level per day)