There are 19 nations, all of which can be human or computer controlled (BTW, the game is ultra-multiplayer friendly), and each of the nations has special Dominions (themes) that give them varient units, among other things.
I've been playing for weeks, but I haven't even seen all the units, let alone explored them all. The spells and items that you have access to are equally amazing. It is . . . highly pleasing.
