Sometimes, I don't want to conquer a city. Most of the times, actually, when I think I have enough cities and I just want to destroy my opponents, I favor a scorch the land approach. In MoO, you could build a planet destroyer. Instead of conquer my enemies, I exterminated them.
What I suggest is not a simple raze the enemy city. I suggest magics that can turn fields into desert or burning lands, that no man can settle, or a frozen tundra that cities can't flourish in. I want  to destroy cities in a way they can't be rebuild, but I don't want to turn all the world into mountains doing this. See, you should be possible to "rebuild" the destroyed tiles, and destroying the world should be costly and time consuming, and everyone should hate you for it, but I think would add a great deal of fun.
Imagine two or more empires fighting each other, between them a vast wasteland that if any unit dare to cross, they cast a rain of destructive magic that destroy and scar the landscape and the units. We should even be able to destroy resources and roads.

Anyway, I just like the possibilities this can have. I dislike maintaining a huge empire, I like a small well optimized empire, but I want the possibility to limit the expansion of other factions.


What do you guys think?