thundering dumbass
A noun used to describe a person who rushes into abnormally stupid activities or situations he/she has no cause to be in or ability to successfully negotiate. i.e. one who "thunders" into stupid shit like a dumbass, hence the term. Usually reserved for those who are dumbasses to such a high degree / perform acts of dumbassery on such a regular basis, they require their own classification.
Al: "I'm going to go fight in a martial arts tournament on Tuesday."
Sal: "Dude, you've never taken martial arts before. You'll get your ass kicked. Why are you always looking for a fight?"
Al: "Nah man I'll fuck up anybody who tries that Judo shit on me"
Sal: "Stop being a thundering dumbass. Just have some drinks with the boys instead."
Al: *proceeds to get his ass kicked on Tuesday*