Ah, I do so love when the contents of the insanity are kind enough to shake things up.
No mage was behind this, I'm afraid. At least not one on any level of yours. If you click this [website], it can explain to you what has happened, more or less.
As for the murder, that sounds like a valiant enough plan- if you can think of any way i could help, do just let me know. Keep in mind, I've no bloody idea what Ferelden is, but. Any excuse for a good ol' murder, I suppose.