Elemental Magic: Shadows Arising

Hundreds of years into a dystopian future, the world was destroyed and remade, and in the process, some humans gained magic. Some could control fire, some could control water, some could control the wind, and some could control the earth. Some could do miraculous healing. Magical humans, known as an Elementalist, would be sent to a school that specializes in their Elemental Magic: fire, wind, water, earth, or healing. Each Elemental school is in a different part of the world, each their Elemental area a 'kingdom'. You're not allowed to step into a kingdom you're not the same element as unless you were given special permission. The only place where you could meet up with a different element safely was in Servi, the only part of the world that wasn't remade, and was a horrible place to be. That was where normal humans, ones that didn't gain magical abilities, were forced to stay. Now, a looming threat of shadowy monsters that will invade the world and kill all its occupants has arisen. Where magic and power and wealth are all that matters and no unity on hand, is the world doomed for destruction?