Brutal B and the Durango Roller Girls will throw their shoulders into one final home bout this season, their third this year. The Derailers will host the Rocky Mountain Roller Girls Project Mayhem at 7:10 p.m. Saturday at Chapman Hill; doors open at 6. Tickets are $10 in advance, $5 for children 12 and under and are $15 at the door. A portion of the proceeds will benefit Frosty Pines, a local wilderness education program for children. Ska beer will be on tap, and food concessions are available.