If that Ganesha-looking thing was owned by Griffith, I wonder how are they planning to make it even, or fair at all. Griffith is just a force of nature at this stage of the manga, so I just don't see a clear way of victory for Guts or anyone in the verse (unless they summon a godlike being such as Shiva or Vishnu I suppose).
And after Miura's death, I have always wondered about the Idea of Evil. Will Mori use that plot point sometime in the future? Who knows, but I am eager to see it return, now that we are talking about "beings outside of the real of demons".