Lycanthropic Curse (Werewolf)

A character who becomes a lycanthrope retains his or her statistics except as specified by lycanthrope type. The character gains the lycanthrope’s speeds in nonhumanoid form, damage immunities, traits, and actions that don’t involve equipment. The character is proficient with the lycanthrope’s natural attacks, such as its bite or claws, which deal damage as shown in the lycanthrope’s statistics. The character can’t speak while in animal form.

A non-lycanthrope humanoid hit by an attack that carries the curse of lycanthropy must succeed on a Constitution saving throw (DC 8 + the lycanthrope’s proficiency bonus + the lycanthrope’s Constitution modifier) or be cursed. If the character embraces the curse, his or her alignment becomes the one defined for the lycanthrope. The DM is free to decide that a change in alignment places the character under DM control until the curse of lycanthropy is removed.

Werewolf. The character gains a Strength of 15 if his or her score isn’t already higher, and a +1 bonus to AC while in wolf or hybrid form (from natural armour). Attack and damage rolls for the natural weapons are based on Strength. The character also gains immunity to bludgeoning, piercing, and slashing damage from nonmagical attacks but becomes vulnerable to silvered weapons (the main weakness for all lycanthropes). 

Keen Hearing and Smell: The PC has advantage on Wisdom (Perception) checks that rely on hearing or smell.

Shapechanger.  The player can use its Action to Polymorph into a wolf-humanoid hybrid or into a wolf, or back into its true form, which is Humanoid. Its Statistics, other than its AC, are the same in each form. Any Equipment it is wearing or carrying isn't transformed. It reverts to its true form if it dies. 

Attacks. Bite (Wolf or Hybrid Form Only). Melee Weapon Attack: +(Str+PB) to hit, reach 5 ft., one target. Hit: (1d8 + Str) piercing damage.

Claws (Hybrid Form Only). Melee Weapon Attack: +(Str+PB) to hit, reach 5 ft., one target. Hit: (2d4 + Str) slashing damage.

If the target is a humanoid, it must succeed on a (DC 8 + the lycanthrope’s proficiency bonus + the lycanthrope’s Constitution modifier) or be cursed with werewolf lycanthrope.

Bloodlust: If under half of the player's total hp. Make a charisma saving throw DC = 16 - PB (Feel free to edit this for your own campaign). If failed whilst in human form, the player shifts into hybrid form and makes a bite attack against the closest creature. If already in hybrid form, the same events occur minus shifting. For the next few rounds, the player will enter a bloodlust, attacking any nearby creatures until it is knocked unconscious or succeeds on the saving throw. (It may be a good idea to allow players to spend their turns talking to the PC to calm them down).  The player repeats the saving throw at the end of each turn.