This post might sound a tad moralistic and angry but I feel compelled to respond to some of the Morrigan worship on these forums that, quite frankly, I don't think the character deserves.
Firstly, let's address the idea of canon endings: no thanks. I would like to make it clear right now that I'd rather not play through the consequences of other people's sadistic choices in the sequel. Let's take the original post as an example. Sariusmonk sees this as canon and a "true" ending:
* Alistair is executed by Queen Anora
* Morrigan is impregnated with demon/god-baby
First of all, I can't even imagine anyone having Alistair executed. Are you kidding me? At the hands of whom? A backstabbing, two-faced Queen who you barely know? Or Loghain, the man who would have had you killed ten times over if he could? And you would sacrifice your only surviving friend after Ostagar, the very same man that has helped you all this time and accompanied you through thick and thin, such a beautifully written character -- you would sacrifice him? And you wish THIS to be considered the canon for the Dragon Age world? I won't have any of that. You can have your orgy of violence and betrayal if you like it, but don't try to tell me that THAT is the way things "should" have turned out. No thanks to the idea of canon endings, Bioware.
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And now let's get to the part concerning Morrigan specifically. First of all, she is a poorly written character among other brilliantly written and beautiful characters. Her entire character and reason for existence can be wrapped up in one simple phrase: "hurr, I'm evil." Even Loghain was more human than she was -- it could even be argued that Loghain had good intentions. A case of the ends not justifying the means and such. But Morrigan? No, sorry, she's about as interesting as your typical sociopath.
Let's take a look at this for example:
Cade Darkspear wrote...
for players that did not help Morrigan
Oh my! For players who did not help Morrigan! Oh, poor Morrigan! How could we not "help" her? Help her by having her sire her demonspawn baby for personal gain? That would essentially make the entire quest meaningless. It would all be for naught. That would have been like coming to the end of LoTR and having Frodo and company hold on to the ring instead of destroying it, you know, just in case it comes in handy in the future. So the very idea that she would have even asked that of me at the end, after all we have been through, was a huge slap in the face. It just went to show how she hasn't changed one bit for all the time that we have travelled together. She would rather all of our efforts have gone to WASTE and risk everything, including the future of Ferelden, for personal gain.
I'm playing an evil character on my second playthrough and I'm "helping" Morrigan out alright -- you know those Dalish elves you encounter in the Brecilian forest? Well, she cheered me on as I decided to slaughter every last one of them. Is this the great character you want to be "helping"? Oh, poor Morrigan! Morrigan is not someone to be "helped" -- she's someone to be sided with. And if you side with her then it's clear that your loyalties do not lie with the future of Ferelden, or with the allies that you have made -- but with some sociopath hell-bent on self-preservation and empowerment. But hey, at least she has huge breasts, amirite? HURR HURR
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For the record, on my first playthrough I had Alistair become King and sacrificed myself at the end. I think it's part of his character development.. the entire game, for me, has really been Alistair's "coming of age" story. And I was proud as **** to see him grow throughout the game and eventually take responsibility and lead Ferelden.
As far as I'm concerned, this was Alistair's story. I was just taken along for the ride, and it was satisfying enough to serve as his mentor and to see him through to the end. But that's just how I see it, and I would not consider forcing that view on others. Which is why I say NAY, GOOD SIRS to the idea of there being a canon storyline.