The Sybil's Crystal (The Peacekeepers of Elysium #1)

Every fifteen years, three divisions of four young people are chosen to compete against each other for the title of "The Royal Guard". And although the upcoming competition is buzzing in everyone's minds, the thoughts of eight individuals lay elsewhere. Their loved ones have suddenly gone missing without a trace, and the eight will not give their search up. But when they are selected, they are forced to step into a new world and forget about their paths. With one unfortunate choice, the eight are forced to travel together despite their distrust for one another. However, with one misstep, the eight discover that they now have a lot more on their hands than a royal competition. And they might have the answers to the mysteries of their relatives. With their discovery, the eight individuals will have to work together to accomplish a mutual goal. They will now have to keep their mission a secret from the rest of the world, and hope that they can save everyone before it's too late.