This can be bypassed if you manage to kill the factions' leadership before attacking the city, through either open battle or assassination. Most of their units are on-par with those of the Elves. Any force of them will be a tough challenge. Third Age: Total War provides examples of:
Of course, there are many sub-mods for Third Age, with two of the most notable being the campaign-focused Divide and Conquer and the multiplayer-focused Third Age: Reforged.
