baiter

noun2

1. •
   Agent noun of bait; one who baits, as a fishhook.

   • The baiter stands amidships, with the bait-box outside the rail: with a tin pint nailed to a long handle he begins throwing out bait, while every man stands to his berth. — 1853
2. •
   (Internet, slang) A troll who deliberately posts aggravating messages on a message board to elicit responses.