Dominion 4 is another game I play that I think I've mentioned on these forums before. Its a single player or online game, turn based, fantasy genre, world dominion by domino effect taking control of territories. Actually the point is that each player is a god and your trying to spread the dominion of that god through the world so you can win if the whole world follows your god irrespective of the secular administration.
The UI is horrid - nothing like Feudums (which is beautiful) and far too complex for novices to get into - but being really very complex has a wealth of features that could be incorporated.
One of the features that can be used is to blood sacrifice your own population to spread influence to neighbouring territories - the idea is that rather than conquering a neighbouring territory you create a religious revolt so the population and any army there overthrow their leaders and defect to you.