Board Thread:General Discussion/@comment-222.127.85.46-20141027120746/@comment-3496661-20141027135156

We haven't forgotten, it just hasn't really been focused on since Season 7, when Epsilon takes the form of Delta, so no one talks about it. Up until Season 12 (or more specifically Don't Say It) Epsilon has only really taken the form of Delta, that's it. He did take the form of the others in Don't Say It but that was only a brief change.

I don't think people have forgotten about it, it's just that since Epsilon only mainly changes into Delta there's nothing really to talk about.