A doppelganger's tactical abilities are limited by their intelligence. So when fighting one someone will have to use skills that can be used more intelligently.
Everyone can have a doppelganger.
You don't become a doppelganger, doppelganger exists by God.
She looked exactly like her, as if she were her doppelganger. She wondered if she had a doppelganger somewhere in the world.
Doppelganger Inc. is no longer existing.
It's because your doppelganger can pretend to be you or she might be standing right behind you when that person saw your doppelganger.
I would consider the antagonist as the creature he is. Not who he is but what he is, a Doppelganger.
Doppelganger - 1997 is rated/received certificates of: UK:PG
The cast of Doppelganger - 1979 includes: Donna Loney
It means that the doppelganger is coming after you or it's trying to tell you something.
Doppelganger - 2009 II is rated/received certificates of: USA:PG
You don't.
Doppelganger