Russian Roulette. Because if I lose, I'm dead anyway, and if I win, then either Death doesn't die because he's supernatural and goes on his merry way, or it turns out that Death can die and I gain his powers (hey, we're assuming Death has a literal form, why not assume supernatural succession?).
And then I would go Kira on the world. Except I wouldn't kill off criminals; I'd kill off morons and assholes.
And then I would go Kira on the world. Except I wouldn't kill off criminals; I'd kill off morons and assholes.