Things to know about Arc Arath:

Elvenia - A parallel universe right beside Earth. In Elvenia there are more than just humans. Elvenia, while not very technologically advanced, has excelled in the art of magic, while Earth has progressed more onto the side of technology. They co-exsist in their universes and are only connected by the Path of Eden.
Path of Eden - The median between the two worlds. The Lunasphere is also located somewhere in the center of the Path of Eden. So far, no living human has ever travelled across it.
Lunasphere - Acts as a bridge between the two worlds. It is assumed that Grandis used the Lunasphere to pass from Elvenia to Earth to attack Uri and the gang. This is the first recorded time someone has used the Path of Eden.
Serena - The Goddess of Fate. Everyone in the known existance of Elvenia knows and loves this being. But because of the Dark Lord, here presence has all been but lost. Her four Guardian Angels despirately seek out those that they would be able to bestoy their magic power to liberate their god from the darkness.
Guardian Angels - The caretakers of the Goddess of Fate. There are four in total, each on representing one of the four major elements: Fire, Thunder, Ice, and Terra.
The Lunis Elru Knights - Two demi-humans, an elf, and human that once lived normal lives in Elvenia that now, through dark forces, serve the Dark Lord and are hell bent on destroying Serena and her land.
Affinity Fragments - The Guardian Angels once created a ornament in the shape of a brooch with limitiedless power that they offered to Serena. But as the Dark Lord decended upon Elvenia, it was shattered. Now the fragments of the Brooch of Affinity, will give it's beholder a boost of power.
Elements - All magic in Arc Arath is divided up into 4 groups: Fire, Ice, Thunder, and Terra. Any Ice based enemy would be weak to Fire. Thunder is weak to Ice, and Fire is weak to Thunder. Terra isn't weak to anything, but takes equal damage from the other three emements. Here is an image to maybe help remind you how this is going to work:

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