race features:
Natural Athlete
You have proficiency in the Athletics skill.
Magma Overflow
(replaces Stone Endurance trait)
As an action, you become a wave of magma that rushes in a staight line up to your movement speed. You pass through the space of any creature along your path, and this movement doesn't provoke attacks of opportunity. You can use this action only if you haven’t moved during this turn, and after you use the action, your speed is 0 until the end of the current turn.
Each creature whose space you pass through must make a Dexterity saving throw against a DC equal to 8 + your proficiency bonus + your Constitution modifier. On a failed save, target takes 2d6 fire damage, or half as much damage on a successful save.
This trait's damage increases by 1d6 when you reach 5th level (3d6), 11th level (4d6), and 17th level (5d6).
Once you use this trait, you can’t use it again until you finish a short or long rest.
Eruption
(replaces the Powerful Build trait)
You have an innate connection to the volcano allowing you to harness its energy, exploding the ground around you. As an action, any creature within 5 feet of you must make a Dexterity saving throw against a DC equal to 8 + your proficiency bonus + your Constitution modifier. On a failed save, target takes 1d10 + half your level (rounded up) fire damage and is knocked prone. On a successful save, a target takes half as much damage and isn't knocked prone.
Once you use this trait, you can’t use it again until you finish a short or long rest.
Volcano Born
(replaces the Mountain Born trait)
You have resistance to fire damage. You're acclimated to high altitude, including elevations above 20,000 feet.