It was instinctive, hereditary and sometimes delightfully impulsive. Once he was sitting at a Las Vegas blackjack table where a boastful Texan was talking loudly about his oil wealth. Mr Packer asked him to quieten down.
"Do you know who I am," the man drawled loudly to impress bystanders. "I'm worth $100 million." Nonplussed, Mr Packer responded nonchalantly: "I'll toss you for it."
The Texan departed. It was no idle challenge. Mr Packer wagered sums that were breathtaking to average people but represented only a small fraction of his personal wealth.
Indeed, the worldwide gaming industry has lost one of its most prolific gamblers with the passing of Mr Packer.
He was the biggest of the roughly 150 international high rollers the industry calls "whales".
In 1987 he won and lost $100 million over three days of the Sydney Easter carnival in a spectacular betting duel with bookmaker Bruce McHugh.
"I held $100 million. Mr Packer placed bets of up to $7 million per race," Mr McHugh said in 2004, breaking his silence 17 years later on the tension of the encounter.
"He ended up winning most of the $100 million back. I finished with $430,000 out of $100 million."
Mr McHugh retired after that exchange, saying he needed a rest.
"[Mr Packer] just kept betting and he just kept winning," he said of the comeback by Mr Packer, who is believed to have been $28 million behind at one stage.
Baccarat and blackjack were the card games Mr Packer enjoyed most and he journeyed around the world to indulge. In 1995 at the MGM Hotel in Las Vegas he had the baccarat section closed and played eight tables alone, wagering between $250,000 and $500,000 a hand.
In 40 minutes he won $20 million and tipped staff $100,000.
In 1997 Mr Packer won $6 million after plunging on Might and Power in the Melbourne Cup.
The next year Mr Packer and his mate Lloyd Williams plunged millions of dollars on Cup winner Jezabeel, cutting the price from $12 to $6.
Gambling was not always so lucrative. In September 1999, Mr Packer was said to have dropped $28 million in a London casino and some Sydney bookmakers are said to have purchased mansions on the water after gambling with Mr Packer on Saturday races.
Only once did Mr Packer go public with his views on gambling and it was motivated by a prod from the unfortunate former leader of the Labor Party, then a backbencher, Mark Latham.
When Mr Packer was reported to have lost $34 million in a casino, Mr Latham, in Parliament, called it "offensive".
Breaking his self-imposed rule of "never complain, never explain" Mr Packer said the loss was much smaller than reported. About $10 million.
"The gambling losses this year is less money than I've given to Westmead Children's Hospital," he said.
"This is not someone else's money. This is my money and I am entitled to spend it any way."
Like the talent in the bloodlines of the champion horses he backed, Mr Packer believed betting was a family heritage.
"My grandfather went to the races [in Hobart] and somebody dropped ten bob," Mr Packer once said.
"He put it on a horse and it won at 12-1. He bought a ticket to Sydney and went into the newspaper industry and did quite well. That's where my family started from, ten bob on a race course."
Mr Packer began his own career as a punter while working at Australian Consolidated Press, then publishers of
The Daily Telegraph. He ran up $10,000 in losses and his irate father paid the debt. When he did it again, his father made him sell his car.
"My father was a gambler," Mr Packer said. "Every man who ever created anything was a gambler."