That's not fantasy, that's just a suspension of disbelief. While you can use a suspension of disbelief in many different genres(including fantasy), that doesn't mean it encompasses all of those elements. Having Two-Face with a burned side isn't technically fantasy, as I've seen many people with severe burns on their skin. It's plausible to live through that, but it most likely wouldn't happen(especially the eye), but that's where you're supposed to suspend your disbelief. Having a man made of clay that can shape shift and mold it's body into anything it wants is fantasy. That will never happen in the real world...ever. Everything that Nolan has presented in his Bat-movies is plausible, so it's just a matter of suspending your disbelief, not going into the realm of the unknown(fantasy).