Kimbo apparently died from heart failure...the same thing that I had. He tested positive for steroids in his last match...more than likely it's left ventricular, which is pretty common from steroid abuse.
Worth noting, despite his gruff exterior and street fighting prowess, Kimbo had a heart of gold as noted in the DailyMail:
'To hurt someone vulnerable, I just couldn't do it like that.
'You want to be a good father and productive citizen. I could have been on the cover of the newspaper as a killer.
'I had to fight with myself not to hurt people, some serious mental wars. But who would have raised my boys? They would have grown up knowing their dad died another violent death.
'They would have been angry, and now, instead of one person dying a violent death, you've got two other little protégés who would have grown up just as violent and vicious, causing even more harm to people.'
This is exactly why I don't do respectability politics. There are people in suits and exalted positions that don't care about harming people or animals...Kimbo was the true definition of a warrior. Here you had a guy that regularly disfigured other men...on equal terms. In other words, he didn't hurt anyone that he didn't have to. I wish our "world leaders" were cut from the same cloth.