Who Said the Lying Owl Blood Contract

Twelve people with different identities were trapped in a century-old owl-singing ancient house, and they were forced to conclude a life-and-death blood contract by the ancient bronze owl statue - those who lie will be cursed and punished by heaven. But everyone in the house has their own hidden secrets, and serial murders are happening one after another. When every word is a disguise and every past is a lie, who is the chess player who has been laying it out for hundreds of years and has hidden the deepest secrets?