I think, in the right circumstances, an ENTP could be the most dangerous. ENTPs can get pretty dark--a lot darker than the other types, when they feel hopeless.
primary Ne = lax expectations of reality
secondary Ti = potential to accept anything that fits into their scheme of logic
tertiary Fe = objective understanding of other people's feelings (what they're feeling--can't always tell why)
least Si = basic awareness of their surroundings
You know what, I've been here, though--struggled through my teen years with untreated ADHD. Wasn't hyperactive. You'd be surprised what growing up with ADHD does to the Ti--I think the only function it really helped was the Ne. ADHD can be useful for enabling executive decision-making when the brain knows the material. The problem is that if it's gone untreated for too long, the brain usually doesn't know because you just don't have the attention span to really get in there and figure anything out. Even if you're able to pick it up intuitively, you lack the fundamental sense of things having structure or purpose.
I could go on and on about ADHD but the point is that if there are any factors which significantly inhibit the secondary function then the person may effectively lose his sense of authorship of his own identity. I've seen it happen to various people on multiple occasions, and they were people with and without attention-deficit disorder. I think this figures into the advancement of symptoms that eventually become anti-social personality disorder more so than almost any internal directive. In the ENTP, it becomes a sort of an impassive disregard for or rejection of reality, supplemented by a talent for superficially blending in while operating as an entirely different personality beneath the skin, which will eventually be skillfully employed when they want human company. However ENTPs derive confidence of their identity from being able to retain flexibility and independence in a world teeming with uncertainties, not from assuming a role of deference to circumstance. Deny them autonomy and opportunities both and they might go to astonishing lengths in their desperation to transcend regulation.
