Cable & Deadpool #30 (2006)

Civil War - The Hero Hunter
Deadpool has heard of the Superhuman Registration Act, has carefully weighed his options, and chosen to operate on the side of those with the lucrative government contracts. After "auditioning" by taking on the Great Lakes Champions (who, it turns out, already registered), he is hired by the government to track down unregistered heroes. He plans to start with Daredevil, but his plans go awry when he learns Daredevil isn't alone.
Release Date: 2006