I love the idea, I've been thinking about it, too.
Howzabout a Trinity Limit-type attack for Roxas, Axel, and Xion? Eh, eh?
I love the idea for the Luxord combo, Sleight of Hand. lol, I bet Luxord never expected to do it on himself.
Well, here goes:
Xemans: Beginning and End - Roxas and Xemnas...