The reverse side of the autumn map is the winter map. You can play any mix of factions on this map, but it is recommended only for experienced players.
Before playing on the winter map, take out the 12 suit markers, flip them face down, and shuffle them.
Then, place one suit marker near each clearing on the map. After a suit marker has been added to each clearing, flip them all over, and set up the game as normal. Note the different placement of ruins, as shown below.
The Raging River
On the winter map, the river divides forests as if it were a path.
On the winter map, the randomness of clearing suits can introduce many new challenges to each faction.
Keep the map's geography in mind when picking factions, and understand that certain factions may gain new advantages and disadvantages in each possible layout.