It only took 10 characters (four of which completed the game - DA:O) to get the Heavy Hitter achievment (Main character deals 250 damage with a single hit). Go figure, the character is only level 15. Of course, it's a mage (although I finished the game once with a mage and didn't get the achievment so... meh.) I think it was the explosion from Virulent Walking Bomb with four mages near each other. But honestly, I had kind of given up on that achievment.
Back to the game. While I have completed the game with a mage before I had not spoken to Cullen in the origin so I didn't see him in the Epilogue. At least, I think that's why I don't see it. On the other hand, I didn't get any Epilogue comments about any of my companions with that character, so maybe I just failed to do important stuff all the way through.