Light Sensitivity. While in bright light, the weasel has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.

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

Telepathic Bond. While the weasel is on the same plane of existence as its master, it can magically convey what it senses to its master, and the two can communicate telepathically with each other.

Unassuming. The weasel has advantage on Dexterity (Stealth) checks.

Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 11 (2d4 + 7) piercing damage. If the target is a creature, it must succeed on a DC 14 Constitution save or be poisoned, suffering 3 (1d6) poison. On a failed save, the target becomes poisoned for 1d4 hours.

Spore Cloud (Recharge 5-6). With a shake of its fur, spores infect the air. Each creature within 10 feet of the weasel must succeed on a DC 14 Constitution saving throw or become poisoned, suffering 6 (2d6) poison damage on a failed save, or half as much on a successful one. On a failed save, the target becomes poisoned for 1d4 hours.

Shadow Teleport (Recharge 5–6). The weasel teleports to an unoccupied space within 30 feet of it, provided that both the space it’s teleporting from and its destination are in dim light or darkness. The destination need not be within line of sight.