Wendigo Matriarch

Pack Tactics. New World Wendigo have advantage on an attack roll against a creature if at least one of the New World Wendigo's allies is within 5 feet of the creature and the ally isn't incapacitated.

Horde Tactics. When more then one New World Wendigo is in combat they do not roll different initiatives and will instead share the same initiative. New World Wendigo also have advantage on Strength checks and saving throws while within 5 feet of another wendigo ally that isn't incapacitated. 

Frightful Presence. Each creature that is within 120 feet of the horde that is aware of it must succeed on a DC 15 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 is immune to the horde's Frightful Presence for the next 24 hours. Minimum number of members required for frightful presence is ten members.

Magic Weapons. The Matriarch's natural weapon attacks are magical.

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

Regeneration. The Matriarch regains 15 hit points at the start of its turn. If the Matriarch takes fire or radiant damage, this trait doesn’t function at the start of the Matriarch’s next turn. The Matriarch’s body is destroyed only if it starts its turn with 0 hit points and doesn’t regenerate.

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

Multiattack. The Matriarch can make three attacks; two with its claws and one with either its antlers or bite.

Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 17 (2d12 + 4) piercing damage plus an extra 11 (2d10) necrotic damage if the target is a creature. A creature must also make a DC 16 Constitution saving throw or gain Wendisism. 

Claw. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 15 (2d10 + 4) slashing damage plus an extra 11 (2d10) cold damage.

Antlers. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 17 (2d12 + 4) piercing damage and the target must make a DC 16 Strength saving throw or become grappled. If a creature is grappled in this way that creature is also considered retrained an the wendigo cannot use it's antlers on another target. 

Deathly Breath (Recharge 5–6). The Matriarch exhales an icy blast in a 30-foot cone. Each creature in that area must make a DC 16 Constitution saving throw, taking 22 (5d8) cold damage and 22 (5d8) necrotic damage on a failed save, or half as much damage on a successful one.

Horde Frenzy. When the Wendigo is within 5 ft. of an ally that has made an attack against a creature it can reach it will use its reaction to make an attack against that same creature.

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

Attack. The Matriarch can make one attack with either its claws or its antlers.

Command the Horde (Costs 2 Actions). The Matriarch can command up to three different wendigo to use their movement and make one attack against a creature of the Matriarch's choice.

Call for the Horde (Costs 3 Actions). The Matriarch lets out a howl that summons 1d4 + 1 New World Wendigo into a space within 5 feet of the Matriarch.