+2 Strength and Constitution.

Wendigo do not have a natural lifespan. Humans can be cursed at any point in their lives, and once cursed they cannot die of old age. They become bigger and more vicious with time, but time will never kill them.

Wendigos are both taller and thinner than most creatures, standing between 8 and 16 ft tall and averaging 500 pounds. You're size class large.

You're fast as ****.
Your walking speed is 50.
With a swimming and climbing speed of 45.

A Wendigo is driven by their hunger and needs, and so they tend towards Chaotic anything but Lawful.

You guard your hunting grounds viciously, and you know every inch and creature within them. When in terrain similar to that of your hunting grounds, you have advantage on wisdom and intelligence checks, and your proficiency bonus is doubled for skills you are proficient in.

Your curse enables you to mimic any sound you've heard in the previous 4 days, including human speech. You know the minor illusion cantrip.

As a creature of the wild, your claws and fangs have acted as your best weapons to take down your prey. When an enemy enters melee, you can choose to use your claws against them, causing 1d6 plus your strength modifier slashing damage. You may also bite them, causing 1d8 plus your dexterity modifier piercing damage.

Fire is your greatest weakness and the only thing capable of killing you. When an attack that deals fire damage hits, the damage is doubled.

Your senses are finely tuned, able to pick up on the crunch of a leaf hundreds of feet away. You have advantage on Wisdom (Perception) and intelligence (Investigation) rolls that utilize your senses of hearing, smell, and sight.

You have Darkvision to a radius of 120 feet and Blindsight to a radius of 30.

You're immune to Poison except for stipulations in the True Carnivore Trait, the Poisoned Condition, Cold, and Diseases.

Your hunger for flesh cannot be satisfied, especially not by fruits and vegetables. Any attempt to consume food that is not meat requires a constitution saving throw. If failed, you become Poisoned, this is the only way you can become Poisoned.