Answer: devilish

AnswerCrossword Clue
DEVILISHFull of mischief
DEVILISHDiabolical
DEVILISHExtremely bad: Colloq.
DEVILISHDiabolical.
DEVILISHMean.
DEVILISHInfernal
DEVILISHMischievous
DEVILISHMephistophelian
DEVILISHInfernal and diabolical
DEVILISHSatanic
devilishVery difficult to deal with or use
devilishOf, like, or appropriate to a devil in evil and cruelty
devilishMischievous and rakish
devilishfiendish (devilishly cruel)