This question already has an answer here:
Is there a term for such a person?
Someone who is a pathological liar, an overt exaggerator. He would want to take center-stage, makes up stories to capture interest, and applies his stated qualities in positive as well as negative interactions.
Such a person, I believe borderlines personality disorder.
But can we summarize him in a word?
Some words that I looked up appear to have different connotations: