Charged Beast

Electric Aura. At the start of each of the Charged Beast's turns, any creatures within 5 feet of it takes 10 (3d6) lightning damage. A creature that toughes the balor or hits it with a melee attack within 5 feet of it also takes 10 (3d6) lightning damage.

Legendary Resistance (5/Day). If the Charged Beast fails a saving throw, it can choose to succeed instead.

Spellcasting. The Charged Beast's spellcasting ability is Intelligence (spell save DC 18, +10 to hit with spell attacks). The Charged Beast can innately cast the following spells, requiring no casting components:

at will: detect magic, dispel magic, lightning bolt, phantasmal force

2/day each: chain lightning, call lightning

Magic Resistance. The Charged Beast has advantage on saving throws against spells and other magical effects

Multiattack. The Charged beast makes three attacks: two with its claws or quills and one with its bite.

Bite. Melee Weapon Attack: +14 to hit, Reach 10 ft., one target. Hit: 27(4d8+9) piercing damage and 25 (3d8+10) lightning damage.

Claws. Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 25 (4d8 + 7) slashing damage plus 25 (3d8+10) lightning damage.

Quills. Ranged Weapon Attack: +14 to hit, range 100/350 ft., one target. Hit: 25 (3d8+10) piercing damage plus 25 (3d8+10) lightning damage.

Decaying Breath. The charged Beast exhales a necrotic poison in a 30 ft. cone. Each creature in that area must make a DC 18 Dexterity saving throw, taking 56 (16d6) necrotic damage on a failed save, or half as much damage on a successful one. If a creature is reduced to 0 hit points by this damage their body instantly rots and dies.

The Charged Beast can take 3 Legendary Actions, choosing from the options below. Only one legendary action can be used at a time, and only at the end of another creature's turn. Spent legendary Actions are regained at the start of each turn.

Claws Attack. The Charged Beast makes a claws attack.

Quill Attack. The Charged Beast makes a quill attack.

Move. The Charged Beast moves up to 25 ft.

Lightning Bolt (Costs 2 Actions). The Charged Beast Casts Lightning Bolt.