User blog comment:Gliscor Fan/Popular Fight - Bad Connections 1: Zatanna vs Scarlet Witch & Gohan vs Superboy/@comment-5035900-20151123023606/@comment-1652808-20151123024147

I think Gandalf vs Dumbledore's rivalry mostly stemmed from Epic Rap Battles of History when people saw the connections and thought "This would make a great fight!"

I haven't seen Lord of the Rings, but from what I understand, it's not exactly a fight I'd want to happen, but it's certainly above most Potter vs Star Wars matchups.

If I had to choose one of them? Juvia vs Katara. I've never really liked the whole "One controls [element], the other is a/an [element]" thing, because after Gaara vs Toph, I've always thought of those fights as huge stomps in favor of the people who control said element (granted, I know little of Fairy Tail and they may be significantly more powerful than some Naruto, but those are my direct thoughts on them)

I might do Juvia vs Katara sooner or later, but unless something tells me something different, I'll always believe that Katara could take it without a whole lot of help.