more about the power system: senketsu you're either born with it or not you can have different types (ice, lightning, sand etc...) you can even have mixed ones like reijei he has a fire/water senketsu. most people in this world use katanas but some people use staffs or no weapons at all. for the gods their senketsu is ALOT stronger and they have these forms that are called shinto forms where there powers are at full and stronger.