The first major addition to Isengard are the Dunlendings. They're cheap raiding units that work a little differently from other similar units. Instead of getting upgraded by the player, they gain their own upgrades as they level. At Level 2, they gain a leader - a fierce Dunlending who grants the horde increased experience gain. At Level 3, Scavenged Armour increases the horde's damage resistance. Finally, they gain Torches at Level 4, which increases their damage against buildings. If Saruman's experience-granting abilities are available, they can level quickly for upgrades.
We are only changing two of Isengard's spellbook powers. Tainted Land is being replaced by Storm of Orthanc. Using this power creates a player-controlled thunderstorm which slows units that are near it. It also generates bolts of lightning that hit and damage enemy units!
More to come in the next few weeks!