When the local metal act Mushroomhead first formed in 1993, few critics imagined the group would still be going at it in 2014. And yet the masked band continues to be popular. Tonight, the local metal band celebrates 30 years of playing Halloween shows with this show at the Agora Theatre. Doors open at 6. Hellzapoppin, Kurt Deimer, Fleischkrieg, Bittersweet Revenge and Twysted Asylum open.