Ancient Leshen

Innate Spellcasting. The Leshen's innate spellcasting ability is Wisdom (Spell save DC 16). The Leshen can innately cast the following sells, requiring no material components.

At Will: Druidcraft

2/Day each: Cloudkill, Dispel Magic, Insect Plague.

1/day: Etherealness, Storm of Vengeance

Legendary Resistance. If the Leshen fails a saving throw, it can choose to succeed instead.

Magic Attacks. The Leshen's weapon attacks are magical.

Magic Resistance. The Leshen has advantage on saving throws against spells and other magic effects. 

Regeneration. The Leshen regains 20 hit points at the start of it's turn if it has at least 1 hit point. If the Leshen takes fire damage this trait doesn't function at the start of the Leshen's next turn.

Totem Stride. Once on it's turn, the Leshen can use 10ft of it's movement to step magically into one of his totems within it's reach and emerge from a second totem within it's territory, appearing in an unoccupied space within 5ft of the second totem.

Multiattack. The Leshen makes two melee attacks.

Claws. Melee Weapon Attack; +12 to hit, reach 10ft, one target.  Hit 25 (5d10+7) slashing damage.

Roots Strike(Recharge 5-6). The Leshen targets up to two creatures that it can see within 90ft of it. Each target must succeed on a DC 17 Dexterity saving throw or take 17 (3d6+7) bludgeoning damage and the target is grappled [escape DC 17]. Until this grapple ends, the target is restrained. When a creature ends it's turn restrained by this power it takes an extra 17 [3d6+7] bludgeoning damage as the roots contact to crush it.

Call Primal Beast (Recharge 6). The Leshen chooses what to summon and attempts a magical summoning. The Leshen can summon 1d6 Primal Murder of Crows, 1d5+1 Primal Wolves or 1 Primal Bear. A summoned creature appears in an unoccupied space within 60ft of the Leshen, acts as an ally of it's Leshen. It remains for 1 minute, until it or it's Leshen dies, or until the Leshen dismisses it as an action.

The Leshen can take 3 legendary actions, choosing from the optins below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The Leshen regains spent legendary actions at the start of it's turn.

Move. The Leshen moves up to it's speed without provoking opportunity attacks.

Claws. The Leshen make one claw attack.

Cast a Spell (Costs 2 Actions). The Leshen casts a spell from it's list of innate Spellcasting, using a daily use as normal.

Call Lightning (Costs 3 Actions). The Leshen targets on creatures that it can see within 120ft of it, the  target must succeed on a DC 19 Dexterity saving throw, taking 44 (8d10) lightning damage on a failed save, or half as much damage on a successful one.