WEC 20: Cinco de Mayhem was a mixed martial arts event held by World Extreme Cagefighting that took place on May 5, 2006 at Tachi Palace Hotel & Casino in Lemoore, California. WEC 20's main event was a heavyweight bout between Brian Olsen and Mike Kyle.
| Actor | Role |
|---|---|
| BBrian OlsenSelf | Self |
 Mike KyleSelf | Self |
| LLodune SincaidSelf | Self |
| DDan MolinaSelf | Self |
| CCory CassSelf | Self |
 Poppies MartinezSelf | Self |
 Glover TeixeiraSelf | Self |
| CCarlton JonesSelf | Self |
| JJeremy FreitagSelf | Self |
| PPaul MorenoSelf | Self |
| KKenny EntoSelf | Self |
| PPhil CollinsSelf | Self |
 Eddie WinelandSelf | Self |
 Antonio BanuelosSelf | Self |
 Rob McCulloughSelf | Self |
| RRandy HauerSelf | Self |
 Nate DiazSelf | Self |
| GGilbert RaelSelf | Self |
| CCassio WerneckSelf | Self |
| AAshe BowmanSelf | Self |
 Fernando GonzalezSelf | Self |
| JJimmy DexterSelf | Self |
 Keith BerrySelf | Self |
| DDonny RiderSelf | Self |