One monster on the list:
BalrogThe Lord of the Rings also made Lev Grossman's list of the six greatest fantasy books of all time, and appears on John Mullan's lists of ten of the best volcanoes in literature and ten of the best chases in literature.
Down in the mines of Moria, things are pretty grim, but something worse than orcs is after the brave fellowship of the ring. It is a big, horrid Balrog, swathed in both darkness and fire, and carrying a whip. Close textual analysis of Lord of the Rings fails to reveal whether it has wings or not.
Read about another monster on Mullan's list.