It was year 2030. People started noticing strange things going on with them: they could control ice, fire or even lightning. People also noticed that they were capable of carrying heavy things that a normal human would never be capable of, or move in superhuman speed. Scientists started studying the phenomena when Aurorans arrived.
Aurora is a planet inhabited by human-like immortal beings. They cannot die, unless their heart is destroyed. Aurorans teached earthlings that the "phenomena" was actually magic, that just arrived on Earth. They also teached humans how to use magic. At first, they did not talk about Drani, until it was impossible to hide it.
Drani is another planet, that has always been Aurora's enemy. It's ruled by a tyrant, who is centuries old, who wanted to spread the destruction onto Earth. Aurorans soon teached earthlings how to defend themselves from Drani, but always leaving room for Earth to defend themselves alone.
A new profession emerged from this situation: the guardians. Guardians are like policemen, diplomats, fighters, all combined so they can guarantee world peace. The leader of the guardians became known as Hikwa, which means "master" in Auroran. One must enter the Guardian Academy to become a guardian. And, to enter the Academy, one must pass the Global Exam.