In 1969, Okada founded Universal Lease, which manufactured coin-operated arcade games for children. In late 1969, Okada's first visit to Las Vegas led to his decision to enter the business of slot machine manufacturing. He invented the "near-miss" feature in his slot machines, an innovation that helped expand the Japanese market of "pachislot" (a hybrid of Japan’s pachinko and Las Vegas slot machines) and also made Okada's slot machines popular in Las Vegas. Throughout the 1990s, Universal served as a major supplier of machines to the bustling Japanese pachinko industry. In 2000 Okada was introduced to Las Vegas-based casino magnate Steve Wynn, eventually investing $380 million in Wynn’s then-new company, Wynn Resorts. Wynn Resorts opened its first casino in 2005 in Las Vegas and a second one in 2006 in Macau. In 2008, Steve Wynn declined to join Okada in a major investment to build a casino in Entertainment City in Manila. Okada proceeded alone with the investment, forming a local company, Tiger Resort, Leisure and Entertainment, Inc., to handle the development of the Manila property. In July 2016, the property was unveiled as the Okada Manila, a $2.4 billion integrated hotel, resort and casino that represents Okada’s biggest investment to date.