4. Kronans
As seen in some of the Thor: The Dark World trailers, Thor smashes a giant rock creature to pieces with a single swing of Mjolir. The rock creature is actually a member of a species that appeared in Thor's very first comic book appearance in Marvel, Journey Into Mystery #83. In that particular story, Thor fought a group or rock creatures known as the Stone Men from Saturn (also known as the Kronans). The Kronans have made a number of other appearances in the Marvel comic book universe over the years, most notably when a Kronan named Korg appeared in the Planet Hulk storyline. It should be noted that the rock creature in the movie is dressed very much like Korg in particular (see below).
Moving on...