Were Lycan (mutated)

Shapechanger. The mutated Were Lycan can use its bonus action to polymorph between it's true hybrid form (3 headed wolf-humanoid) and its huge Direwolf form. Its statistics, other than its AC and walking speed, 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 in its dire wolf form.

Hybrid form: 3 heads and 2 arms and 2 legs.

Wolf form: 1 head and 4 legs, looks same as regular dire wolf but huge.

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

Multiattack. (Hybrid Form Only). The were lycan makes three attacks: two with it's claws and one with it's bite. It can replace one of its claw attack with bite attack or vice versa.

Bite (Hybrid Form Only). Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 8 (1d8 + 3) piercing damage and 4 (1d6) acid damage and the target is poisoned until the end of target's next turn. If the target is a humanoid, it must succeed on a DC 13 Constitution saving throw or be cursed with were lycan lycanthropy.

Claws. (Hybrid Form Only). Melee Weapon Attack: +7 to hit, reach 5 ft., one creature. Hit: 12 (2d6 + 4) slashing damage.

Pounce (Wolf Form Only). Melee or Ranged Weapon Attack: +7 to hit, reach 5 ft., One target. Hit: 12 (2d6 +4) slashing damage. Make a claw attack by moving atleast 20 ft in a straight line towards a target and pounce. Target creating must succeed on a DC 17 Strength saving throw or be knocked prone. Were Lycan can make a bite attack at a prone creature (special). Same bite attack stats as in hybrid form except the constitution saving throw.

Lycan Berserk: If the were Lycan was under 25% of its max hit points it becomes more viscous, it will go berserk and will make all attacks with advantage untill it's dead.

Special: If the were lycan takes more than 30 damage on a single attack, it looses one of its arm or head. 

Acidic Bleed: Purple blood of were lycan is harmful to humanoids. If were lycan is under half of its maximum hit points each creature within 5 ft will take 1d10 acid damage at the start of each of its turn. When were lycan dies, it explodes and every creature within 10 ft radius must make a dexterity saving throw of DC10 or take 5d10 acid damage or half of it if saved.