Since this is upcoming in The Mighty Thor...
Round 1- completely publication history for both... all Shiar and all Asgardians available for both sides, all technology allowed from both sides
Round 2- complete publication history, top 10 Shiar vs Top 10 Asgardians in the arena
Round 3- no Odin, no Thor Odinson, Jane Thor allowed, Cul is allowed (feats post Fear Itself only for Cul), no Loki.
round 4- no odin