Shortly after forming in 1998, local metal band Chimaira signed a deal with Roadrunner Records that effectively launched the group’s career. It achieved national and international fame with 2003’s The Impossibility of Reason, an album that’s every bit as heavy as anything by Slayer or Metallica. The group was on Ozzfest in 2003 and joined the European Road Rage tour that same year. Even after parting ways with Roadrunner in 2006, the band was still a major draw on the metal circuit and its albums still sold well. Two years ago, it reunited to celebrate the 29th anniversary of The Impossibility of Reason, and the band will reprise its annual Christmas show at the Agora. Doors open at 6:30 p.m., and 200 Stab Wounds and Nunslaughter open.