>>102281142Fei Long Reed from Tsubassa Reservoir Chronicles. His plan involved multiple dimensions and timelines, clones, the concept of fate, and lots of memory manipulation. And in the end, his master plan is still unclear.
Xehanort abused used time travel and manipulated a whole bunch of people to acquire multiple host bodies for his soul. He needs the multiple bodies because he's old and wants to see what will happen as a result of the Keyblade War.