Wererat

Heightened Smell. The wererat's Perception is 17 when perceiving by smell.

Pack Tactics. The wererat has advantage on attack rolls against a creature if at least one of the wererat's allies is within 5 feet of the creature and the ally isn't incapacitated.

Multiattack (Humanoid or Hybrid Form Only). The wererat makes three Claw or Shortsword attacks, or it makes three Hand Crossbow attacks. It can replace one attack with a Bite attack, provided it is in the appropriate form.

Bite (Rat or Hybrid Form Only). _Melee Weapon Attack:_ +4 to hit, reach 5 ft., one target. _Hit:_ 7 (2d4+2) piercing damage. If the target is a Humanoid, it must succeed on a DC 11 CON save or be cursed with the wererat lycanthropy curse (see Curse of Lycanthropy sidebar).

Claw (Rat or Hybrid Form Only). _Melee Weapon Attack:_ +4 to hit, reach 5 ft., one target. _Hit:_ 7 (2d4+2) slashing damage.

Shortsword (Humanoid or Hybrid Form Only). _Melee Weapon Attack:_ +4 to hit, reach 5 ft., one target. _Hit:_ 5 (1d6+2) piercing damage.

Hand Crossbow (Humanoid or Hybrid Form Only). _Ranged Weapon Attack:_ +4 to hit, range 30/120 ft., one target. _Hit:_ 5 (1d6+2) piercing damage.

Change Shape. The wererat transforms into a Tiny or Small rat, a Medium rat-humanoid hybrid, or back into its true form, which is Humanoid. Its statistics, other than its size and speed, 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.