RichThesaurus
Mephistophelean
vs
Mephistophelian
Mephistophelean
adj
Showing the cunning or ingenuity or wickedness typical of a devil.
Mephistophelian
How often have the words
Mephistophelean
and
Mephistophelian
occurred in a corpus of books?
(source:
Google Ngram Viewer
)