mephistophelian vs mephistophelean

mephistophelian and mephistophelean both are adjectives.

Word	Noun	Adjective	Verb	Adverb
mephistophelian	No	Yes	No	No
mephistophelean	No	Yes	No	No

As adjectives, mephistophelian and mephistophelean are synonyms defined as:

mephistophelian and mephistophelean: showing the cunning or ingenuity or wickedness typical of a devil

Other synonyms of mephistophelian include devilish, diabolic, diabolical.

mephistophelian (adjective)	mephistophelean (adjective)
showing the cunning or ingenuity or wickedness typical of a devil	showing the cunning or ingenuity or wickedness typical of a devil