I have been playing some games on Monarch difficulty, and I notice there to be a tendancy for the stronger AIs to start vassaling the weaker ones rather than just completely conquer them like I do. It has gotten very frustrating to me, because sometimes I will be in the middle of wiping out a weak foe, and they will surrender to the strong AI who I am trying to beat. I wanted to get some good strategy to avoid this from happening so much. It is very frustrating to have good diplomatic relations instantly ruined with a strong AI when they start protecting a Civ I have already been at war with. Am I better off fighting these strong AIs early in the game to avoid this from happening? Should I be looking real hard when fighting the weak foes to see if they will surrender to me first? For what it's worth, I have noticed this happening a lot on these Pangea maps I've been playing. Perhaps on other map types this wouldn't be as bad. The biggest problem with having all these vassal states is you start up dogpile wars if you want to fight any one of the civs. Sometimes it's those vassal states that make just that handfull of extra troops that is too much for my Civ to handle while I am trying to take on the master Civ. Any advice?