I wonder if Mongols are capable of retraining their uber-experienced units. In my game, I was so worried about letting them grab a castle/fortress/citadel that I basically invited them to focus on cities.

The money they seem to have + ability to retrain heavy lancers and all those missile troops would make them unstopable (+ an aggressive AI, of course... ).

And yes I know the "horde respawn system" from BI (I'm vet player since STW) - but I didn't notice the differences when Mongols settle in MTW2, thank you for that.