Revised Russian Rules:
Russian Revolution: When the Central Powers control 20 or more IPC’s of original Russian areas, the potential for Revolution is activated. Each turn this is accomplished, the German player rolls a die. The first time the roll needs a 6 result to succeed. Each time a new roll occurs, this drops by one.
Effect: When the Russians revolution occurs, they are out of the game. Central power units occupy what they control and Russian units outside of original Russian borders remain as they are and can be attacked, but do not perform any movement/combat. They may defend however. Also, no allied units are allowed to enter in original Russian territories once the revolution begins.