Sorry, I don't know the mechanics of the Horde emergence. I don't believe difficulty level has any effect, there were some theories about the strength of the garrisons present in Khazar/Georgia/V-B in 1230.
You can mod the game to improve the staying power of the Horde, reducing the upkeep for the GH units helps. Not sure how much money they start with on arrival, I assume they start with the usual amount based on difficulty, this could be increased. Using the -ian switch at year 1231 would tell you this value. Another problem is the build requirements for their units, GH Warriors need Bowyer's Guild, GH HAs need Bowyer's Guild and Horse Breeder's Guild, and GH HC need Master Horse Breeder and Master Spearmaker. If the east isn't really built up when they arrive, it is tough for them to replenish their numbers after the initial push.
Bookmarks