Well according to this article, BG3 will use a completely different in house engine from the Original Sin series Seems like a really big project for Larian, and they are taking it very seriously as you can see from this article. Over 300 developers are helming this game, which is the biggest game they've ever created. My guess is it will launch late next year. Anyway, very excited for this game. BG1 was the first PC game I ever played, so to go back to the D&D Universe, Faerun and the City of Baldur's Gate again, is very nostalgic!