Numenera is one of those settings that looks horrible at first glance. 'Fantasy' combined with Sci-Fi is something that always puts me off. It's not that mixing the genre's is bad that it can't be done, but often it's done in such a way I can't help but see the lines between the two. Oh, So the Elves are from the Fantasy side, and look, Power Armor, clearly Sci-Fi. Thankfully, this was about as wrong a first impression as I could have had.
Monte Cook took a brilliant approach by setting Numenera in such a distant future that it hurts to think about. Usually you're thinking about entire generations rising or falling, maybe even kingdoms or countries. Here however, It's entire civilizations, and that includes galactic civilizations. By having such a rich history, There's no reason you can't incorporate basically anything you want in your campaign.
Three legged Monkey Lizards that eat Sand would totally work, but so would Cyborgs, Dragons, Space Ships, Yeti's or basically anything at all. To be clear, these are some rather silly examples, but as I began to read about Numenera I realized that this is where it's power lies. By allowing so much mystery, and making it feel good within the setting, It allows both players and game masters to fudge pretty much anything that would make the game even better.
I'd strongly encourage you to look Numenera over, regardless of your first impressions, and give it a shot. It's currently on the top of my to-play list and I'm very much looking forward to giving it a shot. Regardless of how the mechanics work out, and mind you, they 'look' great, the setting will no-doubt be used as inspiration for my campaigns.