Wendigo

Ambusher. The wendigo has advantage on attack rolls against any creature it has surprised.

Mimicry. The wendigo can mimic any sounds it has heard, including voices. A creature that hears the sounds can tell they are imitations with a successful DC 15 Wisdom(Insight) check.

Pounce. If the wendigo moves at least 20 feet straight toward a creature and then hits it with a claw attack on the same turn, that target must succeed on a DC 15 Strength saving throw or be knocked prone. If the target is prone, the wendigo can make one bite attack against it as a bonus action.

Masks of the Wild. The wendigo can attempt to hide even when it is only lightly obscured by foliage, heavy rain, falling snow, mist, or other natural phenomena.

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

Multiattack. The wendigo makes two attacks: one with its bite and one with its claws.

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 12 (2d8 + 3) piercing damage. On a hit, the target must succeed on a DC 15 Constitution saving throw or take an additional 9 (2d8) necrotic damage.

Claws. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) slashing damage.

The wendigo 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 wendigo regains spent legendary actions at the start of its turn.

Attack. The wendigo makes one attack with its claws or bite.

Move. The vampire moves up to its speed without provoking opportunity attacks.

Frightening Gaze (Costs 2 Actions). The wendigo fixes its gaze on one creature it can see within 10 feet of it. The target must succeed on a DC 15 Wisdom saving throw against this magic or become frightened for 1 minute. The frightened target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target's saving throw is successful or the effect ends for it.