Come on now theres gotta be an answer to this, what is the best/most useful summoning magic in all of the ff'sI know some ff's don't have them, but for those who do.
FF6- Bahamut
7 - Bahamut Zero
8 - Diablos
9 - Leviathan
10 - Ifrit

Oooh looky, the same thread right here (http://forums.ffshrine.org/showthread.php?s=&threadid=14035).