Calladin

Blood Curse of Binding (2/Day). As a bonus action, Kallidin targets one creature it can see within 30 feet of it. The target must succeed on a DC 14 Strength saving throw or have its speed reduced to 0 and be unable to take reactions. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Shapechanger. Kallidin can use its action to polymorph into a dragon-humanoid hybrid or into a dragon, or back into his true form, which is humanoid. His statistics, other than its AC, are the same in each form. 

Keen Hearing and Smell. Kallidin has advantage on Wisdom checks that rely on hearing or smell when he is in his dragon or Hybrid Form.

Blood Frenzy. Kallidin has advantage on melee attack rolls against any creature that doesn’t have all its hit points.

Innate Spellcasting (3/Day). Kallidin can innately cast Hex. His innate spellcasting ability is Intelligence.

Magic Resistance. Kallidin has advantage on saving throws against spells and other magical effects.

Multiattack. The Blood Hunter makes two attacks in Humanoid or  or three attacks in Hybrid Form: two with its Greatsword (humanoid form) or one with its bite and two with its claws (hybrid form).

Bite (Dragon or Hybrid Form Only). Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 6 (1d8 + 8) piercing damage. If the target is a humanoid, it must succeed on a DC 14 Constitution saving throw or be cursed with werewolf lycanthropy.

Claws. (Dragon Form Only). Melee Weapon Attack: +12 to hit, reach 5 ft., one creature. Hit: 7 (2d6 + 8) slashing damage.

Sword of Stigia. (Humanoid Form Only). Melee Attack: +12 to hit, reach 5 ft., one creature. Hit: 8 (1d10 + 2d10 + 8) slashing damage. (if this attack misses you take 2d10 cold damage instead).
Additionally, whenever you reduce a creature to 0 hit points with this weapon you may then immediately cast the spell cone of cold. Once you use this ability you cannot use it again until you finish a short or long rest.  

Cold Breath (Recharge 5–6). Kallidin exhales an icy blast in a 30-foot cone. Each creature in that area must make a DC 16 Constitution saving throw, taking 45 (10d8) cold damage on a failed save, or half as much damage on a successful one.

Draconic Scales. Kallidin can utilize his draconic scales to improve his defense. He gains 2d6+4 temporary hit points.  

Blood curse. When Calladin hits a creature with a melee attack he can activate his blood curse. Taking 1d6 necrotic damage to himself and empowering his attack. You may add an additional 2d8 cold damage to the attack.