Ken Griffin is a mega-successful hedge fund manager who built a massive empire known as Citadel, almost lost it in 2008, and has come back bigger and better than ever in the years since. He's also known for scaring the absolute crap out of employees, counterparties, and various other individuals and groups he comes in contact with, through a combination of a short temper, zero tolerance for the wrong answer, and a stare that could burn the flesh off people's faces in three seconds flat. In a comeback profile of sorts today, the Journal explores this side of his personality, and those who've been lucky enough to experience it first-hand.

There's the higher-up at the firm who learned the hard way which questions are acceptable to pose at Ken and which are not:

With his empire again thriving, Mr. Griffin is working to address a reputation as an exacting and impatient boss, according to current and former employees and others close to the firm. It is a work in progress. Jamil Nazarali, head of Citadel Execution Services, recalls asking Mr. Griffin for his view on how much to bid to acquire a rival. “It’s your f—ing business—how much do you want to pay for it?” Mr. Griffin responded, according to Mr. Nazarali.

Goldman Sachs CEO Lloyd Blankfein, who won't get into super specifics but:

“Even in the context of intense people, Ken would probably be in the top decile of a very rarefied crowd,” said Lloyd Blankfein, the chief executive of Goldman Sachs Group Inc.

And, of course, his estranged wife:

A month after the divorce filing, Mr. Griffin let a moving crew into their duplex penthouse apartment at the Park Hyatt in Chicago while his wife was away. The crew left with furniture and artwork that Mr. Griffin regarded as his own. He also changed the credit cards of the household staff, which includes four nannies for the couple’s three children and a chef who lives nearby. Ms. Dias has asked the court to void her prenuptial agreement and give her custody of the children, with an eye toward moving them to New York. She has claimed expenses of roughly $1 million a month, including the use of two private jets and a six-figure monthly allowance for vacations. Her lawyers have said in court filings that Mr. Griffin told his wife he would sue her until she had no money left and at another point demanded she be a “good girl to him.”

But humans are complex and it would be unfair to paint Griffin as a simply a tyrant who inspires pants-pissing fear in people and makes Steve Cohen look warm and cuddly. Like everyone else, ole KG likes to (sometimes) have a good time and (occasionally) make people feel comfortable. According to the Journal, he sponsored a movie night this past spring and later this year, plans to display skeletons around the office and dunk people in a witch's cauldron, but in fun, carnival-esque way.

Last Halloween, he showed up at work dressed as the Dr. Seuss character the Lorax. He has told some employees he wants to convert part of an office floor to a haunted house this October.

See? It'll be great and a total departure from the mood around the place the other 364 days of the year. Now get the f*ck back to your desks. Candy corn is earned.

Citadel’s Ken Griffin Leaves 2008 Tumble Far Behind [WSJ]