he that mischief hatches, mischief catches
People who behave wickedly receive their just deserts.
QUANT
glint, hint
He had a hint of mischief in his smile when he asked if I wanted to skip work early.
VERB + MISCHIEF
cause, do, make
The children were always causing mischief whenever their parents left them unsupervised.
get into/up to
The kids were always getting into mischief whenever their grandmother wasn't looking.
keep/stay out of
The babysitter warned the children to keep out of mischief while she was upstairs.