How does one of the world's richest men lose more than $30 billion in a single year? With hubris, mostly.

Businessweek's new cover story details the fall of Eike Batista, a brash and boastful Brazilian billionaire whose net worth as of March, 2012 stood at $34.5 billion—just ahead of the Koch brothers.

Then, he decided to start an oil company. Sounded great, at first!

At the end of April 2012, Batista would tell Bloomberg TV that his companies were sitting on $1.5 trillion of “underlying assets.” That amounts to the entire estimated value of all the mineral assets in Mongolia.

As of this summer, Batista's net worth stood at well under $1 billion.

He did not find as much oil as he thought.

Read all about it.

[Photo: AP]