Describe Hit-and-Run Poster here.
The least dedicated (and least sophisticated) breed of Troll, this poster makes one provocative comment, then leaves, never to be seen again. Perhaps he is watching the Internet Backdraft smugly from afar, but not giving the victims the satisfaction of his response; perhaps he just doesn't care -- the satisfaction of knowing someone is pissed off is thanks enough.
Contrast Drive-By Updater, in which the one-time poster actually makes a positive contribution to the wiki. Related to people who ask a question on fora but never bother to come back for the answer.
Because of the requirements of our Creative Commons license, All The Tropes initially disallowed anonymous editing, so we weren't bothered much by them at first. However, we allowed anonymous editing quite a while ago, and sure enough... Even when registration is required, though, we noticed that some Hit-and-Run Posters are willing to go through all the trouble of registering just to get their jollies.