Wikipedia has this for internet troll:

In Internet slang, a troll is someone who posts controversial, inflammatory, irrelevant or off-topic messages in an online community, such as an online discussion forum, chat room or blog, with the primary intent of provoking other users into an emotional response[1] or of otherwise disrupting normal on-topic discussion.


Dictionary.com has this for taunt:
taunt
–verb (used with object) 1. to reproach in a sarcastic, insulting, or jeering manner; mock.
2. to provoke by taunts; twit.

–noun 3. an insulting gibe or sarcasm; scornful reproach or challenge.
4. Obsolete. an object of insulting gibes or scornful reproaches.

Origin:
1505–15; orig. uncert.