in my most recent game (Seljuks) the Mongols whiped out Khwarezmids like it was nothing, and Georgia only survived because i had an army of heavy Horse archers there, that had only just beaten them into submissiveness ... and i still managed to lose a good handfull of cities before i managed to turn the tide by shuffling my Heavy Horse Archers the right places, now defending each city in danger with 8-10 HHA's, half of them born with 3 promos (Barraks, Stable, Theocracy, Settled GG, and whatever the wonder that gives +1 is) which goes into Combat I+II and Skirmish