User blog comment:Jopjopjop/Volume 18 Spoilers/@comment-16281343-20140712201724/@comment-70.186.201.176-20140713234204

I don't think Euclid's defeat was a ploy, but rather he had a plan B and knew with the traitors in the Underworld he coudl escape anytime he wanted anyway. (I think he will actually be defeated by Grayfia when he comes back and that Volume 17 was the end of his battle against Ise).

The author still has plenty of villains left to use so he had to get rid of a few and it sounds like he is planning to introduce some more villains anyway. Don't forget that there is still that crazy Magician lady who's name escapes me.

Also there is still the Nidhog and as shown with the Grendel clones, Rizevim is experimenting with the Evil Dragons.