Ok, so I have a theory. Sorry, I know this is an old topic, but I just figured something out.
Exhibit A: On the description of the Tesla Hammer, it says, "Tesla was a genius. If he ever came BACK to Aethasia...." As far as I know, Nicola Tesla never played Aetherlight. So this must mean someone else.
Exhibit B: As Ariella Newheart pointed out, the picture on the Scarlet City Studio page showed Zaul with the caption Zaul/Tesla.
So.... My conclusion is that when Zaul turns good, (if he is Paul) his name will be Tesla, and that before he turned evil, he invented a bunch of stuff like the Tesla hammer, and when he is good he will give you a bunch of cool stuff. It makes sense, right!