Pack Tactics. The cucco has advantage on an attack roll against a creature if at least one of the cucco's allies is within 5 feet of the creature and the ally isn't incapacitated.
Gliding Flight. At beginning of each round as the cucco is flying, it falls 5 feet. If the cucco is lifting more than its carrying capacity (105 pounds), but not more than it can lift (210 pounds), it falls 15 feet per round instead. If the cucco is attempting to carry more weight than it can lift, it falls 60 feet per round, similar to feather fall. The cucco will drop anything heavier than 420 pounds. The cucco cannot gain height with its flight unless it is carrying nothing.
Surprisingly Strong. Cuccos are remarkably powerful for their small frame, able to carry more than a hundred pounds, even if only temporarily. No one is quite sure how they manage this.
Vengeful Flock. Cuccos live in large family groups known as flocks. While normally peaceful and cowardly, they can quickly become dangerous in great numbers. If a cucco is under attack by a predator, it will call out to its feathery brethren to attack the assailant. As if from nowhere, dozens of cuccos will appear and descend on the unlucky foe.