User blog comment:GotMilk5101520/How will the Tartarus Arc Part 4 will end?/@comment-24247034-20140709220536/@comment-25111584-20140710212447

Deliora has been implied to be able to enter his Demon form, it'd be quite difficult to defeat him then. And Jellal himself acknowledges that Ul would most probably have been a Wizard Saint if she had been alive. I'd say she was stronger than even his current self, but just my conjecture. We'll never really find out, unless Jellal does actually help Gray.