User blog comment:B j/Battle Royale/@comment-5126917-20120611122409

I did have similar thought, Bj. After all the event on the last day is still marked as "???". It is possible that on the last day, all participants from all teams will have to battle each other all out and gaining points from every single opponent from other teams that they defeated. But, in the end, just like what you wrote, let's leave them to Mashima's imagination.