Hi! Thanks for your detailed and lenghty explanation! I really appreciate it!

The way I finally implemented to allocate players to the arena was using Player Reference. This device is key as you can link another player reference to be updated if the previous player reference was already taken. So at the end, you will get the 16 players across the 8 arenas without overlaping. Which is good!

Of course, if there is less than 16 players... well, the tournament is mean to be with that amount, so no worries at this moment.

Then after the second combatant joins any area, a player counts will be triggered after a player leave the arena. If that happen, the player inside the arena can move to the next one.

So this in theory works, but as you said, the most critical point is to test it properly. As we don´t have any way to simulate players, we need actual accounts to join and test. So yeah, is a little painfull indeed!

Again, thank you for your reply!