Unlucky Cat

Keen Smell. The cat has advantage on Wisdom (Perception) checks that rely on smell.

Bad Luck Comes in Threes.  When an attack is made against the unlucky cat, it can choose to make the attacker reroll the attack with disadvantage.  If it does, the unlucky cat has disadvantage on its next attack roll.  This feature can be used three times before the unlucky cat must complete a long rest.

Snake Eyes.  If an attack roll made by, or against, the unlucky cat rolls a critical 20, it cants as a 1 instead.

Walking Under the Ladder.  The unlucky cat can choose to make any attack with disadvantage.  

Black Cat Crossing.  Melee Weapon Attack: +5 to hit, reach 10 ft., one target.  Hit 6 (1d6 +3 necrotic damage.  If the unlucky cat makes this attack with disadvantage and misses, the target must make a DC 12 CHA saving throw.  On a failed save, the creature is frightened until the start of the unlucky cat's next turn.  This cannot frighten creatures that are Huge or larger.

Claws. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d4 + 3) slashing damage.