1) Enormously, obscenely, filthily rich, and living in preposterous comfort on his own planet in a galaxy filled with aliens;
2) The only homo sapiens alive who actually remembers the 20th century, as he spent most of his early centuries cryogenically frozen on one starship after another, and thus lived long enough to reap the benefits of radical life extension technology once it was invented; and
3) The avatar of a god in an extraterrestrial pantheon. When the book introduces this point you need to PAY ATTENTION because it turns out to be really important later, unlike some of the scenery setting early on which doesn't serve much of a purpose beyond giving some local color to the universe.
Isle of the Dead was my first-ever Roger Zelazny novel, picked up in a used bookstore when I recognized the name and thought, "Zelazny? Sounds familiar. I think I ought to read him".
It's only 190 pages, but it packs more weird ideas than most SF novels three times its length. It could so easily have been padded out, and in today's market it almost certainly would've been. Heck, if I found out that Isle of the Dead had originally been 600 pages and its current length was a result of merciless editing, I would've believed it. As it is, I feel like I've read a delightful artifact from an earlier time when being succinct was nothing to be ashamed of.
The last two used SF paperbacks I read, the Harrison and the Sheckley, were both written as light fluffy comedies, and I'm not dissing that. I like light fluffy comedies. Zelazny, though, delivered a short little novel written with some mighty literary style. That meant I couldn't just breeze through it as quickly as I'd planned, but I'm not complaining. Zelazny has impressed me, and now that I have a better idea of what to expect from him I'm looking forward to reading some more.