Assertion: mollusk's shell | /r/HasProperty | heavy to move
Facets:
Source sentences:
text: Curiously, Bulbapedia states that the shell of Omastar was too heavy to move and this led to the species extinction (they died out from starvation).
text: Shells are heavy structures, so few vertebrates aside from turtles and a few armored mammals bear them; instead, most shelled creatures are invertebrates.