The Skinny: It takes greatness to headline two different rock festivals in one weekend. Slipknot stormed the Monster Energy Aftershock Festival in Sacramento, CA on Saturday, October 24, 2015, and then on Sunday, October 25, they were the closing act (appropriately) at Knotfest, in San Bernardino, CA. On Sunday Slipknot saved their own sick party by playing a set that blow every other one of the day’s main stage acts to smithereens