Apex Wendigo

Regeneration. The Wendigo regains 50 hit points at the start of its turn. The Wendigo body is destroyed only if it starts its turn with 0 hit points and doesn’t regenerate.

Invisibility. The Wendigo is invisible at night, heavy storm and or blizzard . 

Mist Stalker. The Wendigo has advantage on stealth check and give disadvantage to the players perception and Investigation checks. 

Soundless. The Wendigo actions, movement and spellcasting produce no sound. This means when the Wendigo attacks a player by themselves , move through the environment and cast any spell they know produce no sound at all. When the Wendigo physical attack any creatures, those creatures will lose all ability to produce any sound.

Prey Tracking. The Wendigo knows the distance to and direction of any creatures it hunts, even if the creatures and the Wendigo are on different planes of existence. If the creatures being tracked by the Wendigo dies, the Wendigo knows. 

Freedom of Movement. The Wendigo ignores difficult terrain, and magical effects can't reduce its speed or cause it to be restrained. 

Spellcasting. The Wendigo is an 18th-level spellcaster. Its spellcasting ability is Wisdom (spell save DC 20, +12 to hit with spell attacks). The Wendigo has the following druid spells prepared:

Cantrips (at will):  Frostbite, Mold Earth, Infestation, Control Flames, Earth Tremor, Gust

1st level (4 slots): Charm Person, Entangle, Fog Cloud, Snare.

2nd level (4 slots): Hold Person, Gust of Wind, Earthbind, Pass without Trace. 

3rd level (4 slots): Tidal Wave, Dispel Magic, Counterspell, Meld into Stone.

4th level (4 slots): Charm Monster, Confusion, Hallucinatory Terrain, Ice Storm . 

5th level (4 slots): Tree Stride, Wrath of Nature, Transmute Rock, Freedom of the Winds. 

6th level (4 slots): Transport via Plants, Move Earth, Wall of Thorns, Sunbeam. 

7th level (4 slots): Finger of Death, Whirlwind, Plane Shift, Mirage Arcane. 

8th level (6 slots): Control Weather, Tsunami, Feeblemind, Sunburst, Earthquake, Power Word Stun. 

9th level (4 slots): Storm of Vengeance, Foresight, Shapechange, Power Word Kill.

Multiattack. The Wendigo can makes 7 attacks: one with its bite, two with its claws, one with its horns,  two with its  tentacle and one with its tail.

Bite. Melee Weapon Attack: +19 to hit, reach 10 ft., one target. Hit: 36 (4d12 + 10) piercing damage. If the target is a creature, it is grappled (escape DC 20). Until this grapple ends, the target is restrained , and the Wendigo can’t bite another target.

Claw. Melee Weapon Attack: +19 to hit, reach 15ft., one target. Hit: 28 (4d8 + 10) slashing damage.

Horns. Melee Weapon Attack: +19 to hit, reach 10ft., one target. Hit: 32 (4d10 + 10) piercing damage.

Armor Tail. Melee Weapon Attack: +19 to hit, reach 20ft., one target. Hit: 24 (4d6 + 10) bludgeoning/piercing/poison damage. If the target is a creature, it must succeed on a DC 20 Strength saving throw or be knocked prone. 

Armor Tentacle. Melee Weapon Attack: +17 to hit, reach 30 ft., one target. Hit: 20 (3d6 + 10) bludgeoning/piercing/poison damage, and the target is grappled (escape DC 18). Until this grapple ends, the target is restrained. The Wendigo has 4 tentacles, each of which can grapple one target.

Frenzy Hunger. When you take damage from creature within range of your attacks,  you can use your reaction to make an attack against that creature.