Even though Hulk Hogan was of the biggest heels during his time leading the nWo during his time at WCW, Eric Bischoff revealed that Hogan struggled at first being a heel.
Bischoff recently talked with Sports Illustrated's "Extra Mustard" section, and Bischoff revealed that Hogan was nervous about how the crowd will react to him turning heel after being the biggest babyface in wrestling for many years. According to Bischoff, Hogan drew inspiration from his fellow peers on being an effective heel such as Jesse 'The Body' Ventura and Roddy Piper.
"Hulk got very comfortable in that heel role, but initially, it was very hard for him," Bischoff said. "He was so unsure how the fans would react after being so familiar seeing him as a babyface for so long. There was a big part of Hulk Hogan that loved being a heel, and once he connected to that character, and once the audience connected to that character, he thoroughly enjoyed it. Hulk, as a top babyface for nearly 15 years, had the opportunity to work with some of the greatest heels in the business. He saw a lot of things that he filed into his 'heel folder', and that included drawing from 'Superstar' Billy Graham, Jesse 'The Body' Ventura, and Roddy Piper. He'd had the opportunity to work with some of the best heels in the business, and he filed a lot of that away. There was also a part of Terry Bollea's real personality that he brought to the table that allowed him to let loose."
Hogan turned heel at the 1996 Bash at the Beach pay-per-view, joining Scott Hall and Kevin Nash to form the New World Order. You can read the full interview at this link, where Bischoff talked more about Hogan.
Bischoff returned to WWE at the 2017 WWE Hall of Fame to induct Diamond Dallas Page.