Slipknot's massive, two-day/two-state event, Knotfest, begins today in Council Bluffs, Iowa, and concludes tomorrow in Somerset, Wisconsin. The band has released the video above as a tribute to their late bassist, Paul Gray, and a teaser for those who'll be watching the Somerset show online. (Buy pay-per-view access here.)

Are you going to Knotfest? If you're there, share your pictures, stories, etc. with us - email us at [email protected] and we'll publish the best stuff next week!