The Lunaric Chronicles: Legend of the Wielders

In this low fantasy tale, a self-secluded teen named Elden is forced out of his bubble. He, along with his cousin Amanda and five others are chosen to be one of seven wielders. Given the powers of the elementals, they're tasked with fighting back the army of the darkness, destroying the gateway to the dark world, and saving the planet. Only time will tell if they are up to the challenge.