Answer: upsetter

AnswerCrossword Clue
UPSETTERDisturber.
UPSETTERTroublemaker.
UPSETTERSpoiler
UPSETTERHot sauce, to some stomachs
upsetteroverturned
upsetterto defeat
upsetterdisturbed
upsetterupsetting or being upset
upsetterone who upsets (to overturn (to turn over))
upsetterto distress emotionally or physically
upsetterdefeat
upsetterto knock over