1) Agitator 2) Badgerer 3) Blusterer 4) Disturber 5) Fomenter 6) Heckler 7) Hellhound 8) Hellion 9) Hoaxer 10) Inciter 11) Instigant 12) Instigator 13) Loudmouth 14) Prankster 15) Provoker 16) Rioter 17) Tricker 18) Trickster 19) Troublemaker 1) Bad hat 2) Mischief-maker 3) One who makes extra effort 4) Persona non grata 5) Trouble maker 6) Troublemaker 7) Unwelcome person 
• (n.) One who troubles or disturbs; one who afflicts or molests; a disturber; as, a troubler of the peace.
troubler 1. Someone who deliberately stirs up trouble. 2. A troublemaker.