吠える拳 (Hoeru Ken): Through training, meditation, and perhaps some supernatural assistance, you have learned to harness your ki to suppress the curse of lycanthropy that runs through your blood, and even transform yourself at will. However, overuse of this power can come at great physical cost. You can spend 1 ki point to transform into a werewolf hybrid form as an action. At the beginning of each of your following turns, spend 1 ki to sustain the transformation. You can revert to your normal form as a bonus action.

In your werewolf form, you can utilize all your Monk class features, including the ones powered by ki. If you end any of your turns in werewolf form and have no ki points remaining, you will be forced back into your normal form and gain one level of exhaustion. You cannot transform again until all levels of exhaustion from any source have been cleared.

When transformed, you gain the following features: 

Feral Form: You gain temporary hit points equal to 25% of your max HP, rounded down. If your default size is Small, you become Medium sized.

Lycanthrope Resilience: You have resistance to bludgeoning, piercing, and slashing damage from nonmagical attacks not made with silver weapons. While you are not wearing armor, you gain a +1 bonus to your AC.

Predatory Instinct: You gain a +1 bonus to attack rolls made with your unarmed strikes.

Bestial Reflexes: You gain advantage on Dexterity checks and saving throws.

Bite: This attack replaces Unarmed Strike. Deals (1D8 + DEX Bonus) piercing damage on a hit. When you damage a creature with your bite, you regain a number of hit points equal to your Constitution modifier (minimum of 1 hit point).

Claws: This attack replaces Unarmed Strike and Flurry of Blows. Deals slashing damage on a hit equal to your current Martial Arts damage die + STR and DEX bonuses.