As I continued reading, I found that he started hating Eris more and more. It was something without any proof that he arbitrarily decided upon. It probably counts as a type of unjustified hatred.[6]
And it seems that Eris gradually became unable to beat him. Was it because he got stronger, or was it because of age that Eris became weaker? I can't tell from what's written. In the end, 'that' time came.