Many people would get confused on the order of Opus, Fable and Mythos. In my mind, they are even from different groups; fable is a synonym forba fairytale (perhaps with songs), mythos is communicating importance and status instead of a size, while opus is the only one which in my mind communicates a big size. "What did you think about the Tolstoy's book? It was not a book, but a real opus, a tedious, incomprehensible, sluggish monumental opus."

Oh my god I’ve got it!

Bug < Ticket < Story < Epic < Theme

Waiting on Limerick to drop.