Battle for Middle Earth
A larger version of the Minas Tirith battle, good guys start with Gandalf the White Aragorn Faramir and some archers, bad guys get witch king on foot catapults Grond troll drummers a small army and a
army of Mumakil and Haradim to the south. For maximum fun do not launch main assaults instantly, just small battles over central land, and do not use Grond until 15 minutes into the game. Enjoy.