 He competed in SuperAstros as El Merenguero until the show went off the air in August 1999 and left the company.After being released by the WWF Castillo joined the newly formed International Wrestling Association (IWA) in Puerto Rico and reunited with Los Boricuas Savio Vega and Miguel Perez.During this time Castillo began to use the Hardcore wrestling style and often used the ring bell against his opponents.