Ratling (5e Creature)
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Tiny monstrosity, chaotic evil
Sense Magic. The ratling senses magic within 120 feet of it at will. This trait otherwise works like the detect magic spell but isn't itself magical.
Sneak Attack (1/Turn). The ratling deals an extra 3 (1d6) damage when it hits a target with a weapon attack and has advantage on the attack roll, or when the target is within 5 feet of an ally of the ratling that isn't incapacitated and the ratling doesn't have disadvantage on the attack roll.
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d4 + 3) piercing damage.
The ratling has the body of a rat, but sharp teeth, a hateful, human-like face and paws like tiny human hands. The origin of ratlings is unknown, but it is most likely unnatural. Ratlings are said to speak all languages known to man.
Based on Dreams in the Witch House by HP Lovecraft.