Volibear, The Relentless Storm

The Relentless Storm. Volibear's Claws, Thundering Smash, and Frenzied Maul attacks deal an extra 20 (4d8) lightning damage (included in attacks) and are magical. The lightning from these attacks arcs to up to 4 other creatures within 15ft. of the target, who must make a DC 17 Dexterity saving throw or take the same lightning damage; *Creatures wearing or wielding metallic equipment have a -3 to this save*.
They Have Lost Their Wild. Volibear's attacks deal double damage to man-made structures and objects not worn or carried.
Magic Resistance. Volibear has advantage on saving throws against spells and other magical effects.
Legendary Resistance (3/Long Rest). If Volibear fails a saving throw, he can choose to succeed instead.
The Vrestrom Consumes All (Mythic Trait; Recharges after a Short or Long Rest). If Volibear is reduced to 0 hit points, he doesn’t die or fall unconscious. Instead, he erupts with chain lightning, regains 200 hit points, and recharges Stormbringer (at half damage).

Multiattack. Volibear makes three attacks: one with Thundering Smash and two with his Claws.
Claws. Melee Weapon Attack: +15 to hit, reach 15 ft., one target. Hit: 18 (2d8 + 8) slashing damage plus 20 (4d8) lightning damage.

Thundering Smash. Melee Weapon Attack: +15 to hit, reach 15 ft., one target. Hit: 20 (2d10 + 8) bludgeoning damage plus 20 (4d8) lightning damage. Target creature must succeed a DC 18 Constitution saving throw or be stunned until the start of Volibear's next turn.

Frenzied Maul (Recharge 5-6). Volibear attempts to bite and maim a creature, leaving a lasting wound. Target creature must succeed a DC 22 Strength saving throw; Target creature takes 16 (2d6 + 8) piercing damage plus 20 (4d8) lightning damage and is wounded for 1 minute on a failure. Target takes half damage and is not wounded on a success. Volibear heals for half the total damage dealt if he targets a wounded creature.
Wounded: creature receives half healing and takes an extra 8 (2d6) piercing damage. Condition can be removed via lesser restoration, a DC 14 Medicine check with a healer's kit, or a DC 18 Medicine check.

Sky Splitter (Recharge 4-6) Volibear hails a massive lighting strike to himself. Creatures in a 20-foot radius sphere centered on Volibear must succeed DC 22 Constitution saving throws, taking 30 (6d8) lightning damage or half as much on a success.  Volibear gains 4 (1d6) temporary hit points for each creature in the radius.

Stormbringer (1/Short or Long Rest). Volibear leaps through the air, gathering the peak of his elemental fury, before crashing down in a 30-foot radius dome at a location of his choice within 60ft. of him. Creatures within the dome must succeed DC 23 Constitution saving throws taking 60 (10d10) lightning damage and those in a space he lands on take an additional 48 (8d10) bludgeoning damage and are paralyzed for 1 minute on a failure. Creatures take half damage and aren't paralyzed on a success. A paralyzed creature may repeat the save at the end of their turn, ending the effect early on a success.

Pursuit. Volibear drops on all fours, dashing toward an opponent he can see or hear.

Oncoming Storm. Volibear can make an attack of opportunity when a creature enters or exits his melee range. If the creature dashed to enter his range he adds +2 to the attack roll.

If Volibear’s mythic trait is active, he can use the options below as legendary actions for 1 hour after using The Vrestrom Consumes All.

With Tooth and Claw. Volibear makes two attacks: one with his Claws and one with Frenzied Maul.
Unrestrained Voltage (Costs 2 Actions). Each creature within 60 feet of Volibear must make a DC 25 Dexterity saving throw, taking 15 (6d8) lightning damage on a failed save, or half as much damage on a successful one. Until the start of his next turn, Volibear gains a +4 bonus to AC and creatures that hit him with a melee attack while within 5 feet of him take an additional 12 (4d4) lightning damage.