In stage 1:
LP
Taking Back Sunday [again]
Serj Tankian
Snoop Dogg
Johnatan Davis
In stage 2:
Stylef Of Beyond
Avenged Sevelfold
Slipknot
Scars On Broadway
Other
Featurings:
Snoop Dogg in a hip hop medley with mike
John singing osc
A surprise show, with serj and scars playing soad
Cover:
Maybe a Korn cover, like Blind or Freak On a Leash
Or a Black Sabbath song, like The Wizard, Iron Man...
Lol, it's a dream, but can be possible ^^