Blighted Gorthok the Thunder Boar

Relentless (Recharges after a Short or Long Rest). If Gorthok takes 42 damage or less that would reduce it to 0 hit points, it is reduced to 1 hit point instead.

Blight Presence. Corrupted by the Blight, Gorthok has a frightening presence that intimidates even the strongest of spirit. Any creature within 120 feet of Gorthok, and is aware of him, must succeed on a DC 18 Wisdom saving throw or become frightened for 1 minute.

A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature gains immunity to any Blight Presence for the next 72 hours. 

Legendary Resistance (3/Day). If Gorthok fails a saving throw, it can choose to succeed instead.

Multiattack. Gorthok can make 2 attacks, any combination of the following: 

Lightning Charge. Gorthok moves at least 10 feet toward a target, bashing his lightning infused tusks against it. The target takes 2d8 + 5 (14) lightning damage. If the target is a creature, it must succeed on a DC 15 Strength saving throw or be pushed up to 10 feet away and knocked prone. 

Lightning Tusks. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 12 (2d6 + 5) slashing damage plus 7 (2d6) lightning damage.

Thunder Hooves. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 12 (2d6 + 5) bludgeoning damage plus 7 (2d6) thunder damage.

Tusk Parry.  Gorthok adds 6 to its AC against one melee attack that would hit it. In order to do so, the enemy must be in front of him, within his line of sight. 

Swift Turn (1x/round). Because his vision is limited, Gorthok may need to reposition to face his attacker. Once per round, when Gorthok takes damage from a melee weapon, he spins to face his attacker. All creatures within 10 feet of of Gorthok that are in his path must succeed on a DC 16 strength or dexterity  Saving Throw (player choice) or be pushed up to 10 feet away. 

Wheek!  The first time that Gorthok goes below half health, he makes a loud WHEEK, crying out for the aid of the Blight. This removes all debilitating effects and he gains 70 (5d12+37) health. 

Thunder Stomp (2/day). Gorthok starts to stomp, kicking up dust and causing thunderous vibrations within 30 feet, centered on himself. Each creature in that circle must make a DC 16 Dexterity saving throw, taking 66 (12d10) thunder damage and becoming paralyzed for one round on a failed save, or half as much damage on a successful one. On a successful save, the creature is not paralyzed. 

Lightning Bolt (3/day) Gorthok shoots a bolt of lightning at one creature it can see within 120 feet of it. The target must make a DC 16 Dexterity saving throw, taking 36 (8d8) lightning damage on a failed save, or half as much damage on a successful one.