If we ever do 1v1 Fight Club stuffs for this game, how do we do that?

possible ideas
1. 2vs2vs2vs2.... in custom arena.
2. No attack/fight until purple items are crafted.
2. All comes to forest's camp as they finish crafting.
3. Conduct 1vs1, ally resurrects a downed ally who lost in 1v1.

Any better ideas?