World Series of Fighting 29: Gaethje vs. FosterWorld Series of Fighting 29: Gaethje vs. Foster was a mixed martial arts event held on at the Bank of Colorado Arena in Greeley, Colorado.BackgroundThe event was headlined by a WSOF Lightweight Championship fight between champion Justin Gaethje and Brian Foster. It was originally expected to take place at Budweiser Events Center in Loveland, Colorado, but on January 23, WSOF announced that it would take place at Bank of Colorado Arena in Greeley, Colorado.