I'm an ENTP
ENTPs are usually verbally as well as cerebrally quick, and generally love to argue--both for its own sake, and to show off their debating skills. ENTPs tend to have a perverse sense of humor as well, and enjoy playing devil's advocate. This sometimes confuses, even angers, those who don't understand or accept the concept of argument as a sport.
"Clever" is the word that perhaps describes ENTPs best. The professor who juggles half a dozen ideas for research papers and grant proposals in his mind while giving a highly entertaining lecture on an abstruse subject is a classic example of the type. So is the stand-up comedian whose lampoons are both funny and incisively accurate.
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I've studied Myers-Briggs pretty extensively over the past 4-5 years and belong to a few forums on it. It's pretty crazy how accurate it is.
From what I've noticed, I feel like most people on this forum are INTJs. And the one's doing the trolling are ENFPs and ENTPs.