Zeljko Ranogajec is an Australian gambling legend and arguably the most successful professional bettor of all time. Known for his extreme secrecy, he built a global betting empire focusing on horse racing, sports betting, and lotteries. Ranogajec reportedly wagers billions of dollars annually, using sophisticated computer models, data analytics, and rebate programs to maintain an edge. Despite avoiding the public eye, his influence is felt across the betting industry, with many bookmakers adjusting their systems to counter high-volume bettors like him.