I kind of like the whole "Kain is being manipulated by Golbez, who is being manipulated by Zemus, who is in turn being controlled by his anger: Zeromus" that FFIV had going on.
But really, none of these character come close to ExDeath. He manages to take out the first set of Crystals in World One without even having a body, half the time getting the protagonists to do most of the work for him. He then takes out the rest of the Crystals in world 2 in much the same way, followed by merging the worlds back into one (manipulating dimensions is quite a lot of manipulation). Then you think he's dead by OH SNAPZ HE'S STILL ALIVE HE TURNED HIMSELF INTO A THORN.
You know I can't really remember why Exdeath is manipulative now, but he's such a tank that there is no way he couldn't be the absolute greatest at everything. Man Exdeath is awesome. I'm going to go jerk off to how awesome he is.
brb