Till now, I have seen about 10 different planets, from various trailers and presentations.<p>Clearly the game doesn't have 18*10^18 unique planets, since this is impossible. The problem this game has is, does it have enough variance in its planet generation, so that the average player will not notice a pattern.<p>The planets I have seen all looked mostly the same, with slightly different color schemes and animals made from generic pre-built parts. Unless the devs are only showing a couple of percent of the game, getting the 10 random samples from the game, all of which show a very similar planet is almost impossible.