Notes - this isn't the full power planet size Eonar but rather her building size form seen in the leaks. Ra-den is at full power. Using post Old God buffed Deathwing and the strongest version of Onyxia and Nefarian. Ragnaros is in his Legged form. Using the 4 horsemens in Legion. Nozdormu isn't allow to use his time cheats. Location takes place in a huge arena. If the winning group suffered casualties, they would be resurrected for the next round. The water elemental lord would have a large poud for him to use.
Round 1
group 1
Ragnaros, Neptulon, Thearzine, and Ak'kir vs Malygos, Alexstrasza, Nozdormu, and Ysera.
group 2
Lich King Arthas and the 4 horsemens vs Eonar the Life Binder.
group 3
Deathwing, Nefarian, and Onyxia vs Kil'jaeden and Archimonde.
group 4
Tyr, Odyn, Helya, and Ra-den vs the Seven Prime Sha
semi finals
Winner of group 1 vs winner of group 2
Winner of group 3 vs winner of group 4
Finals
The winner of the last two remaining teams would fight each other.
I expect everyone to have different results. Not just who would eventually become the champion but also which team loses and wins their battles? Which team moves on? Which team would eventually get 1st place?