Legend in his own mind 

An individual who experiences grandiosity, with probable undertones of liberal to severe narcissism. Someone who thinks that they hold an immense amount of clout in the world when in reality they hold very little, or likely, none.

Don: I'm telling you man, when I got down on the scene everybody knew who I was. Shit I got the hookup for everything and anything.

Phil: Wow, there goes Don talking shit again. He don't know shit about shit. That dude is a legend in his own mind.

Legend in his own mind by Phil Fernandez December 5, 2016

Legend in his own mind 

A dumb ass that thinks he is smarter than anyone.....but screws up everything they touch or attempt...a person who acts like they know what there doing, even though they do not....this includes dumb ass people , morons, and guys who where jackets with tassels hanging off them....

Hey check out that guy in the tassel jacket and moccasin boots, hes a Legend in his own mind !!!!

That guy is such a tool , he's a Legend in his own mind, telling me how to do my job !!!

Girl , he's a Legend in his own mind, cause that 4 min of sorry sex was nothing like what he said he was gona do to me !!!

Legend in his own mind by Heyman3000 February 12, 2010