Shapechanger. The werewolf can use its action to polymorph into a wolf-humanoid hybrid or into a wolf, or back into its true form, which is humanoid. Its statistics, other than its AC, are the same in each form. Any equipment it is wearing or carrying isn't transformed. It reverts to its true form if it dies.

Keen Hearing and Smell. The werewolf has advantage on Wisdom (Perception) checks that rely on hearing or smell.

Multiattack. (Humanoid or Hybrid Form Only). The werewolf makes two attacks: one with its bite and one with its claws or spear.

Bite (Wolf or Hybrid Form Only). Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 6 (1d8 + 2) piercing damage. If the target is a humanoid, it must succeed on a DC 12 Constitution saving throw or be cursed with werewolf lycanthropy.

Claws. (Hybrid Form Only). Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 7 (2d4 + 2) slashing damage. 

Howl of the Damned. : Anyone that comes within' 20 feet or is in that rage must make a Wisdom saving throw (DC 14) or be frightened. Lasts until saving throw can be made

Legendary action (4 per day)

Elemental Rage: On it's attack the were-beast can make an elemental base attack, changing it's form as well. 

Fire: The abomination's form shifts, it's body glowing with red flame along with its maw glowing with red flame. It can make a bite attack with an additional (1d6 burning damage). It also leaves a trail of scorched earth as it walks, anyone who steps on the trail must roll a Constitution saving throw or take an additional 1d6 (halved is succeed) 

Ice: The abominations form shifts once more, it's form crystalizing with ice and mist, it's fur being matted with ice and frost. It can now make a frost claw attack, (additional 2d4 cold damage), and upon a successful hit, the target is stuck for one turn in its current spot.

Earth: The abominations eyes swell with black energy, dust and dirt crumbling from it's form as it now deals an extra (1d8) bludgeoning damage. Upon a hit, a wall of stone appears in front of victim, 15 feet in length. 

Wind: The abomination's hair spikes up, its eyes glowing with blue energy. Deals an additional (1d6) and the target is knocked back 20, and all targets in 10 feet take 1d4 damage upon a failed dex save.