The Witcher Bestiary - Cockatrice
Cockatrice Occurrence: Cockatrices nest in caves and dark cellars.

Immunity: High resistance to poisons; difficult to knock down.

Susceptibility: Sensitive to silver and Ornithosaur Oil.

Tactics: A cockatrice tries to surprise its opponent, strike suddenly and poison him with its venom.

Alchemy: Toxin, cockatrice eyes, and feathers.

Cockatrices are born of eggs laid by roosters consorting with other roosters. The egg must be incubated for forty-four days by a toad, which is devoured by the little beast as soon as it hatches. A cockatrice hates everything that lives so fiercely that its glance turns the living to stone. Only a bold adventurer with a mirror can deflect its deadly gaze and defeat the cockatrice.