Board Thread:Questions and Answers/@comment-7401186-20141209064121/@comment-25364614-20150817105844

Some people get unnaturally touchy on this site. I can only ask that everyone not put themselves on a slight higher pedestal than other people (unless they are saying crazy things).

As for an answer to your question, The Omnipotent One, herald has given an answer for you in another thread (posted here for convenience):

Herald of meridian wrote: You can't really say that there's a "strongest" character in the Index Universe, mainly because every character has another character that can defeat him, and even the broken Magic Gods were taken out by Aleister, Noukan and Kamisato Kakeru.

And if that isn't enough, then the best guess would be either Aleister, Noukan or Aiwass. But I'm being really rough with that guess.