The various DnD games were built on a game engine done by Bioware.
I may be getting forgetful in my old age, but I thought NWN used the Aurora Engine rather than the Infinity Engine? Unless Aurora is the 3d version of IE?[/quote]
First of all, as you said, "various DnD games", trully, weren't built on a game engine done by Bioware. The first studio was SSL with their brilliant Pool of Radiance: Ruins of Myth Drannor, later was Westwood with Eye of Beholder, later Black Isle and today (after pack years) Bioware.
Second, ofcourse whole NWN's uses Aurora, but various versions. And ofcourse Aurora is next version of 2nd IE.

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