deviltry

from WordNet (r) 3.0 (2006)

deviltry
    n 1: wicked and cruel behavior [syn: {deviltry}, {devilry}]
    2: reckless or malicious behavior that causes discomfort or
       annoyance in others [syn: {mischief}, {mischief-making},
       {mischievousness}, {deviltry}, {devilry}, {devilment},
       {rascality}, {roguery}, {roguishness}, {shenanigan}]

from The Collaborative International Dictionary of English v.0.48

Deviltry \Dev"il*try\, n.; pl. {Deviltries}.
   Diabolical conduct; malignant mischief; devilry. --C. Reade.
   [1913 Webster]