Spy Catcher, Feed The Rhino, Mad Dog also added to the bill
Festival will also host a book of remembrance for late bassist
Masked metallers return to the stage for the first time since the death of bassist Paul Gray
Vocalist pays tribute to late friend in ink: 'I miss him so much' - video
Joey Jordison posts heartfelt message to best friend Gray
Frontman says he is 'going to swear and sweat a lot'
Wilson opens up about the uncertain future of the masked metallers
Singer to promote 'Seven Deadly Sins...' with acoustic gigs
However, Joey Jordison says Slipknot will carry on with or without Taylor
Singer says he is 'nowhere near prepared' for summer tour