I've said it before, and I'll say it again: the characters. True of every single game and DLC. Bioware has done a marvelous job of creating a world and populating it with real people, from major players like Alistair and Morrigan and Anders and Varric to the villains and anti-villains, from significant NPCs and the quest givers who pop up in the most unexpected places to the random extras who lurk in the background. You get the sense that even the tiniest of bit players have a story, a reason that brought them to that time and place. Even the less well-rounded characters still have some purpose and/or interest to them. I have my quibbles, as I've mentioned on days when I've had to pick least favorites, but there is no one I would ditch entirely.
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