A lot of in this thread switch that one around a bit, believing that the Old Gods and Forgotten One's are the same since in the lore the Old Gods gave the Magisters the power to Kill arlathans which at the time still prayed to the creators. and the fact that with abyss you can infer that means Underground. which makes us again believe they are the same.
And in the Lore the Creators lived in the Eternal city/Heaven so when the legend says "nd they trusted him when he said that they must keep to the heavens while he arranged a truce" means the Creators stayed in the Eternal City at the time he locked them up.
I'm not saying your theory is wrong, i just want to see how you defend against these differing opinions to explain why your theory might be true.
Also you spell Fen"Harel. you just needed to switch the A and E. Also just because I'm a dread wolf fanboy and think he is the Elder One. you should look at all the Wolf statues shown in the trailers and such. and considering how much Fen'Harel is mention in TME, and DA2 and with the fact in DA redemption they showed The Mask of Fen'Harel which could tear the Veil.
Yeah, it was actually reading a lot of the posts that got me to thinking and I remembered the story from Merril in DA2. Maybe she was wrong, but maybe not.
It is true that the legend says there was a truce, but the elves lost everything when they were enslaved. It could very well be that they remembered it wrong or just like legends in real life it changes with the telling and possibly there is more than one legend of what happened. There are often multiple legends about the same thing and each has an element of truth.
Also I can see why there would be a connection between Underground and the Abyss. And I do think that what the Tevinters worshiped was the Forgotten Ones. I just think that history got it wrong where their gods were imprisoned. Instead of the Old Gods being the archdemons that became corrupted it was instead the other Old Gods that were imprisoned in the Fade. This would still work with the Old Gods giving them blood magic to destroy the elves because the elves worshiped their archenemy the Creators. The mythos doesn't really change much in that respect, but only the location.
Oh, and while I didn't mention it in my first post I totally think Fen'Harel has a part to play in all this. After all he was the one that imprisoned them so he would totally have an interest in that prison being broken. Just what part he plays in all of it though I don't know. But yeah, totally going to be involved some how. (At least if this is even partly true
which who knows I may be wrong). I don't think he is the elder one because while Fen'Harel is a lot of things I don't think he is the personification of arrogance.
Fen'Harel does have the power to tear the Veil, but he has been free the entire time. Why now? And if he has this power who is to say that one of the other gods couldn't learn how to do it. While it may be an inherent talent of Fen'Harel to tear the Veil, it could be something that one of the Forgotten Ones could learn. But because it is not something that comes naturally to them this would account for the violence of the tear since it isn't something they have done before. This could also explain why it took so long to act.