Board Thread:Questions and Answers/@comment-24385550-20140329204934/@comment-3235402-20140401152248

I think it might be Diagon. Wasn't the "Old One" at some point revealed to be Diagon, either in the show or by the writers? Diagon's return in Omniverse would be neat, considering his buildup as a major villain, and then abrupt defeat by Vilgax. (Possibly relevant: Vilgax's squid monsters looked like Lucubra-Vilgax-Diagon.