Mephistophelian in a sentence as an adjective

I just do not want to subscribe to the idea that for the rest of eternity you have to make a mephistophelian bargain in order to '10x'.

Mephistophelian definitions

adjective

showing the cunning or ingenuity or wickedness typical of a devil; "devilish schemes"; "the cold calculation and diabolic art of some statesmen"; "the diabolical expression on his face"; "a mephistophelian glint in his eye"

See also: devilish diabolic diabolical mephistophelean