Ha, ha---maybe the Far Side of the roof:
"...Basilisks were supposedly born out of a rooster's egg that was hatched by a viper or toad. Although seemingly invulnerable, Basilisks had two great enemies: the weasel and the rooster. Weasels are immune to a basilisk's glare and venom, and kill the reptiles mercilessly. In addition, merely hearing a rooster's crow kills a basilisk..."