Obnoxisity
Acting like you're the only one who ever existed, especially when you're wrong.
'You think you're smart? I'm the only one who matters.', said by someone who got a 40 on the test.
'I don't even need to explain it. You're just too dumb.', said by someone who didn't even know the question.
'You're not even worth my time. I'm the only one who's real.', said by someone who couldn't even spell their own name.