Unfortunately at the moment we are a bit behind on documentation (sorry about that, we’ll get to it soon-ish)
Simultaneous Elimination works thusly:
When the tournament starts we divide the players into groups, within those groups everyone plays each other in round robin fashion… at the end of a round only the top 1 or 2 from each group will advance, everyone else will be out of the tournament (there’s no consolation bracket). We then re-group people for the next round and it happens over again until no one is left but the top player.
This is one of those cases where it would be good to have documentation because this type of tournament really only works well for hundreds of players because so many are eliminated at the end of each round. This tournament exists primarily to support some of the old title tournaments from original OGS. One of our next big work items is to overhaul the tournament system which will include true single and double elimination tournaments and most likely the simultaneous elimination tournament will go away for regular users… or have much steeper start requirements. In fact, this tournament is unlikely to be startable at all until at least 100 people have joined it so you folks may be waiting a while.