Aa...asharazalalala XD here's some idea in my head.
The legend is as follow: there's the prophecy that the Evil One would come and destroy the world. There, a Hero would rise and, with allies, destroy the force of evil. The Hero would wield the Holy Sword Magius, as the Evil One wielded the Demon Sword Deus Teribles. They are a polar opposite, the Dark and Light. It is prophesied that if the Hero slayed the Evil One, its force would vanish and the world would return to peace. However, if the Evil One managed to defeat the Hero, everything would fall to ruin.
The villain is a typical Evil One-like (imagine Sauron from LOTR). The name is One of Million Thorns, prophesied as the Evil who will destroy the world. The history is that few years ago, a portal opened in the westernmost reach of the land, and from there sprung forth monsters shaped nothing like the inhabitants of this world. They destroyed everything on their path. Each place they've invaded changed into their dimension. Their goal would be complete dominance.
At this threat the world kingdoms rallied their troops into an united front, going on a holy crusade against the coming Demons. But even after years of fighting, victory seemed so far from hand. Heroes and mercenaries arose and went their separate way to fight the Evil. Many fell, but people still believe that one day, the Hero would come and defeat the Evil...
We can start as recruits in the world army trying to fend off the demons, or a separate group going independently to try our luck against the evil. I'm thinking of having only a small group, 3-5 people to reduce dying chance XD not like I think it can live long but I think I'll rather try than sulk :<