After you take the southern half of the map, build a siege factory somewhere. Send the army west to get a few Settlements, including one where you can build an Outpost. Once all the cav are dead, it's time to grab some territory. Keep your guys together, and wait for them to come to you. Plus, they're stupid, and they won't attack all at once. It's a ton of cav, but a good portion is archer.

Eventually (after about 7 minutes), Rohan reinforcements will come. Keep your entire army tight at your Castle. His Fireball and Wizard Blast powers won't kill too many, but it will cause enough havoc to give your archers time to blast them. As it is, the cav will totally trample everyone, so it may be a good idea to put Saruman in the lead. There might be a battalion of cav archers, which are much better to your survival. Within a couple minutes— if that— a few battalions of cav will come after you.

Your priority is defending yourself from the Rohan attacks that will be coming soon. You may notice that you can build a siege factory for the first time, but don't worry about it yet. You'll still probably take a bunch of casualties, though. Saruman's army is probably stronger than Lurtz's, so you should be able to survive longer. The thing is, they're loaded with cavalry, and you haven't had much of a chance to get pikemen. The objectives are fairly easy: wipe everybody out. Saruman is a better hero than Lurtz, so take Saruman's army into this.

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