Catman vowed revenge against Luthor, and was subsequently recruited into a criminal syndicate known as the Secret Six. Together, the Secret Six waged war against the Secret Society of Super Villains under the direction of an individual known only as Mockingbird. During that time he found out that it was in fact fellow Secret Six member Deadshot who had killed his lions, so that he would join the organization. Deadshot would later apologize, and Catman forgave him. Although the two were reluctant allies at first, the two soon bonded and became what one could loosely call friends.