http://littlewargame.gamepedia.com/TournamentGuidelines

Veto system is as follows: (bo3 until finals, Bo5 for finals)

>Each player will veto a map from the pool below until only one map is left remaining

>For the second map, the loser of the first picks the map from any of the maps other than the first map played.

>For the final map, if it is played, the loser of the second map chooses any map that hasn't been played allready in that set.

>Ravaged

>Expedition Lost

>Village of the guards

>Overgrowth

>Cloud Kingdom

>Oasis Valley

>Whirl way