The singer's former bandmate Tony Iommi admits at the height of the band's hellraising days Ozzy decided to go crazy with a dead shark because the group weren't excited by drugs anymore.
Tony said: "With drugs always you get bored, so you must do something to one another. Like Ozzy hauling a shark through a window, dismembering it and soaking our room in blood."
The 63-year-old guitarist - who has just released his memoirs 'Iron Man: My Journey Through Heaven And Hell With Black Sabbath' which details his life with the band - now accepts his own drug use caused problems in his life, but he insists he was able to get sober without going to rehab.
He added to the New York Post newspaper: "We had management problems, I married four times. Was a lousy husband. I suddenly didn't feel good, so I stopped drugs. No rehab. I'm a country squire I live on a farm with dogs and chickens. All I want is to work. I'm dedicated to working. Listen, I've set up equipment inside an enormous dungeon in a huge castle in Wales. And worked. I felt creative."
Tony is still in regular contact with Ozzy, 62, and insists the pair are good friends.
He said: "I talk to Ozzy couple times a week. He's up, down. I love him, although his attention span lasts three seconds."
The shark incident is not the only occasion where Ozzy has misbehaved with an animal.
On 20 January 1982, he bit off the head of a bat that was thrown on stage while performing at the Veterans Memorial Auditorium in Des Moines, Iowa, a moment that has gone down in rock 'n' roll infamy.
In 1981, an intoxicated Ozzy bit the head off a dove and spat it out during a meeting with record executives in Los Angeles. He had planned to release The Doves into the air as a symbol of peace.