Fox

The fox has advantage on Wisdom (Perception) checks that rely on hearing or smell.

If the fox moves at least 20 feet straight toward a creature and then hits it with a claw attack on the same turn, the target must succeed on a DC 9 Strength saving throw or be knocked prone. If the target is prone, the fox can make one bite attack against it as a bonus action.

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

Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 (1d4 + 2) slashing damage.

The fox adds 2 to its AC against one opportunity attack that would hit it.