At the
2006 South American Games, Castillo lost to
Hamilton Ventura in the semifinals and ended up with a bronze medal. At the
2007 Pan American Games, he won 15:5 against
Carlos Negron, but lost to the eventual winner
Eleider Alvarez 8:10 in the semifinal. He failed to qualify for the
2008 Summer Olympics and went up to heavyweight, winning a silver at the
2011 Pan American Games. At the
2012 Olympic qualifier, he lost 8:14 to
Michael Hunter, but qualified for the Olympics on the strength of "two wins vs no-names". He lost in the first bout at both the
2012 and
2016 Olympics. He represented Ecuador at the
2020 Summer Olympics. ==Notes==