Whichever way the wind blows, he goes opposite.
In his normal form, he’s a grey, nondescript humanoid. Of course, he can assume any other humanoid’s shape at will, and has a personality that can accurately be described as every one of those shapes blended together.
You battled the doppleganger in a vicious midnight battle against Maugrim’s dire wolf and his fellow packs. Although the doppleganger assumed the form of Turansul and managed to foil almost all your efforts to distinguish between the two of them, he was foiled at last when you discovered that he could conjure clothing at will, but not other material items.
He was then found to be the same bloke that tattooed rainbow skin into Colbicus, who then persuaded Davian to release him. He hasn’t been seen since.