User blog comment:Omega natsu2/Chapter 372: Breach, Predictions./@comment-24536822-20140215073714/@comment-7418318-20140215155026

Gray didn't beat Doriarte with his childisch imagination. He beat the Demon by redirecting the magic from Silver's ice into Doriarte.

While Jackal is a lot smarter than Doriarte, he still isn't the sharpest knife in the drawer, so Romeo might be able to trick him once or twice. But I doubt that'd be enough to really beat someone of Jackal's calibre. Especially with the way that Jackal just shrugged off many of Natsu's attacks.