Base Class: Barbarian
In the days when the planes were still young, the Lady Moon and the Lord Sun ruled over the whole of the Feywild. They often fought, and bitterly so, so when the Lady Moon was found to be having an affair with the Wolf Spirit, it was of little surprise. The children born of this tryst were the first shifters -- lycans whose blood thrummed with bestial fervor and arcane energy, with the ability to willfully transform between man and wolf. The Lord Sun, enraged by this indiscretion, banished their children to the Material Plane, and placed a curse on them: her children would lose their ability to control their own transformations, and when the moon became full and Lady Moon's gaze was at its widest across the Material Plane, she would be made to watch them transform into hideous beasts, hunted by humans seeking to wipe the menace from their communities.
The Feywild was then split into the Court of Night and the Court of Day -- later they would become the Courts of Winter and Summer, respectively. It would not be for thousands upon thousands of years, when the primordial dust had settled and the planes grew stable that they were able to reclaim some of their descendants; but by then, the curse had spread, and the reputation had been sown. Through the combined efforts of Mother Moon and Father Wolf, they were able to heal their children to some degree, but by then, the curse was so ingrained in their existence that they could not cure it fully. Shifters regained the ability to willfully transform themselves, but found that in times of great duress, they would still become the bestial monsters that the Lord Sun had made them.
Shifters are not just werewolves: they are lycanthropes of fey descent, who use their monstrous nature to their advantage in battle. Many learn to channel their strongest emotions into combat, fulfilling the need brought on by the curse of bloodlust. Shifters who do not learn to control themselves often find themselves in dire situations, where they have either terrorized villages and must live with the guilt, or hunted down by the communities they were once a part of. Even when well-managed, the life of the Shifter Barbarian is often a lonely one, as they find themselves shunned for their heritage. Most try to keep their identities a secret, and those who don't turn to a life of adventuring.
Kindred Spirit
Though your heritage has dictated your future, it bestows you benefits when interacting with your biological kin. At 3rd level when you adopt this path, you gain the ability to cast the animal friendship and speak with animals spells, but only on canines. Work with your DM to determine what animals are considered appropriate for this ability.
Blood of the Wolf
At 3rd level, when you adopt this path, you gain the guidance of the Wolf Father and Mother Moon. While you’re raging, your friends have advantage on melee attack rolls against any creature within 5 feet of you that is hostile to you. Your heritage makes you a leader of hunters.
Aspect of the Beast
At 6th level, you learn to harness the wolf blood in your veins to transform into the beast itself, and can take one of two forms.
Rage Shift
While raging, you gain the ability to turn into a wolf-man hybrid. You gain two natural attacks: Bite (reach 5 ft., one target. Hit: 1d8 + 2 piercing damage. Trip.) and Claws (reach 5 ft., one creature. Hit: 2d4 + 2 slashing damage. Finesse.) You gain +2 AC, but when attacked with magic or silvered weapons, you must make a Constitution saving throw equal to the attack roll. On a failure, you lose Resistance to bludgeoning, piercing, and slashing damage until your next turn.
Wolf Shape
As per the Druid's Wild Shape ability, except you may only transform into a wolf. You are able to stay in this form for a number of hours equal to half your Barbarian level. You are able to use this ability twice per long rest.
Spirit Walker
At 10th level, you can cast the commune with nature spell, but only as a ritual. When you do so, the spirit of the wolf appears to you to convey the information you seek.
Ferocious Presence
At 14th level, as a bonus action, you can attempt to intimidate your foe into submission. It 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.