Barbarian: Path of the Storm Herald

Original Source: Xanathar's Guide to Everything

Storm Aura

^{3rd-level Path of the Storm Herald feature}
Starting at 3rd level, you emanate a stormy, magical aura while you rage. The aura extends 10 feet from you in every direction, but not through total cover.

Your aura has an effect that activates when you enter your rage, and you can activate the effect again on each of your turns as a bonus action. Choose desert, sea, or tundra. Your aura's effect depends on that chosen environment, as detailed below. You can change your environment choice whenever you finish a Long Rest.

If your aura's effects require a saving throw, the DC equals 8 + your proficiency bonus + your Constitution modifier.

Desert. When this effect is activated, all creatures of your choice in your aura take Fire damage equal to half your Barbarian level, rounded down.
Sea. When this effect is activated, choose one creature you can see in your aura. The target must make a Dexterity saving throw, taking 2d6 Lightning or Thunder damage (your choice) on a failed save, or half as much damage on a successful one. The damage increases when you reach certain levels in this class: 3d6 at 5th level, 4d6 at 9th level, 5d6 at 13th level, and 6d6 at 17th level.
Tundra. When this effect is activated, you and each creature of your choice in your aura gains a number of Temporary Hit Points equal to one third your Barbarian level (rounded down) plus your Constitution modifier as icy spirits inure it to suffering.

Storm Caller

^{3rd-level Path of the Storm Herald feature}
Also at 3rd level, you gain the ability to manipulate the elements that flow through you. When you finish a long rest, you may choose a cantrip from the environment you chose for your Storm Aura. You may cast this cantrip while raging. Constitution is your spellcasting ability for these spells.

Desert. You learn control flames, gust, or produce flame.

Sea. You learn gust, shape water, or jolt.

Tundra. You learn gust, ray of frost, or shape water.

Storm Soul

^{6th-level Path of the Storm Herald feature}
As in Xanathar's Guide to Everything except the following:

Sea. You gain resistance to lightning damage, and you can breathe underwater. You also gain a swimming speed of equal to your current walking speed.

Desert and Tundra can both be activated as a Bonus Action instead of an Action.

Shielding Storm

^{10th-level Path of the Storm Herald feature}
As in Xanathar's Guide to Everything

Raging Storm

^{14th-level Path of the Storm Herald feature}
As in Xanathar's Guide to Everything except the following:

Desert. On a failed save, the creature takes fire damage equal to your Barbarian level and begins burning, taking 1d10 Fire damage at the start of each of its turns; on a success, it takes half damage and does not begin burning. The creature cannot end the Burning condition while in the aura, and once it does, the saving throw DC is the same as above.

Sea. Prompting the saving throw no longer requires a reaction, but can only be activated once per turn. Also allows the creature to be knocked up to 15 feet away from the barbarian.

Tundra. That creature must succeed on a Constitution saving throw or become Chilled until the start of your next turn. While Chilled in this way, its speed become 0 and it cannot take Reactions as magical frost covers it.