Mephistophelian vs devilish

Mephistophelian

devilish

adv

  • Devilishly; very; exceedingly. 

adj

  • Resembling a devil. 

  • Extreme, excessive. 

  • Characteristic of a devil. 

How often have the words Mephistophelian and devilish occurred in a corpus of books? (source: Google Ngram Viewer )