That's a really long time to be stuck. There is some information on beating various end bosses somewhere, I think under Story and Lore, where you might find information you are looking for. It's a lot to churn through and not all of it is useful, but if you ask on the threads there that apply, someone might see it and give you a reply that'll be what you need.

It's getting someone to see you ask there that might be a problem. I never check in those but if you send me a note, I'll see that