Dude, I don't even... fucking what? I love both games but they're not even remotely similar. What the hell is this comparison about?
One is a semi-SRPG (isometric) with heavy SMT style (monster allies, etc.), the other is a freaking ARPG in which you use equipped bottlecap-pins to attack.
I guess maybe you're likening the plots? But that comparison is as tenuous as comparing the plots of Duke 3D and Commander Keen because they both have aliens. There are hundreds of games with doomsday plots, why would you link these two as if they were siamese twins? Next thing, you'll be telling me that Star Craft II is Quake IV done right.