Path of the True Dragon

There are few creatures in all of creation that match the awesome might and legendary status of a true dragon.  Some say there are mortals born with the souls of these legends, their power barely contained until it explodes to the surface.

Draconic Attunement

At 3rd level you learn the language draconic if you don’t already know it. When you finish a long rest, you can choose one of the following damage types: fire, lightning, acid, poison, or ice.  You gain resistance to that damage type until you conclude another long rest.  In addition, while you're raging, the first creature you hit on each of your turns with a weapon attack takes extra damage equal to 1d6 + half your barbarian level. The extra damage is the same type that you gain resistance to from this feature.

Acid

Acid is the element of black and copper dragons.

Cold

Ice is the element of white and silver dragons.

Fire

Fire is the element of red, gold and brass dragons.

Lightning

Lightning is the element of blue and bronze dragons.

Poison

Poison is the element of green dragons.

Legendary Resistance

Beginning at 6th level, if you fail a saving throw, you can choose to succeed instead.  You can only use this ability once each day, regaining its use at dawn.  You gain a second use of this ability at level 12 and a third when you reach level 18.

Frightful Presence

Beginning at 10th level, you can use your action to frighten enemies with your frightful presence. When you do so, choose any number of creatures that you can see within 15 feet of you. If the creatures can see or hear you, they must succeed on a Wisdom saving throw (DC equal to 8 + your proficiency bonus + your Charisma modifier) or be frightened of you until the end of your next turn. On subsequent turns, you can use your action to extend the duration of this effect on the frightened creatures until the end of your next turn. This effect ends on a creature if it ends its turn out of line of sight or more than 30 feet away from you.

If the creature succeeds on its saving throw, you can’t use this feature on that creature again for 24 hours.

Legendary Rage

While raging, you can take a legendary action, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. You regain spent legendary actions at the start of your turn.

Attack. You make a single melee weapon attack.  This attack benefits from the extra damage granted by your Draconic Attunement feature.

Dash. You take an extra movement. This movement does not trigger attacks of opportunity. 

Detect. You make a Wisdom (Perception) check.