The game has been thoroughly tested for 2-4 players. With 5 or 6, further testing is needed, but it appears minor changes will allow for play:
72 and 84 tiles for 2-4 players / 105 tiles for 5 players / 126 tiles for 6 players.
"WoTA" its expansion which add a new special mechanic to the game (with big crystals).
With "Expand" - there are only tiles that have the same function like in basic game, there are special tiles like teleports, exmitters and trading post but nothing new. "Expand" increases time of the game if you wanna to do this.
With adding more wormholes in 5 or 6 players game it's only our suggestion. So if you have only 4 wormholes in 6 players game im sure that two or more players dont get wormhole pass whole game, but the game doesn't crash because of that :)