Standard spells are Fell Strength and Black Ice, which boosts your troops and slows down enemies, respectively. The Sorcerer has a straightforward close-combat attack, but his spells are his most potent weapon.
Of the new units, the most interesting is the Sorcerers of Angmar. The rest of the ground forces consist of: the inordinately powerful Snow and Hill trolls Dark Rangers, which are ranged units, naturally Dire Wolves, who are large and fast the Troll Stone Thrower, a siege weapon and the magnificent Sorcerers. The thrall master can summon spearmen and orcs to aid him, while the Black Numenoreans comprise a majority of the general ground units. Most of the units start off pretty meekly, but they can be built up to tough, gritty, and all-around hardy enemies. The new faction, Angmar, is brutal, vicious, and built for straight-out combat.
Skirmish mode has also received upgrades and boasts smarter multiplayer A.I.
The War of the Ring mode brings changes to the world map economics and siege weapons are instituted, and armies in RTS mode are now also viewable from the isometric view. RotWK provides many new additions to the original game, including a new faction (the Angmar), many new troops for existing factions, a revamped War of the Ring mode, new character classes for the hero builder, and a new Angmar campaign.