The assassin hero

There are four cardinal heroes, the hero of the spear, the hero of the bow, the hero of the sword, and the hero of the shield...but there's one more hero that the kingdom tried to hide in the shadows. Their is a fifth cardinal hero, the hero of the knife or also known as the assassin hero. His stories, myths, and writings were destroyed because every hero who has held this title had their loyalties lied with the people instead of the monarchy and it's nobles making him an enemy them. Now the cardinal heroes are needed again but only the four main cardinal heros, but what happens if the fifth shows up. Will he rebel against the kingdom that needs his help, or will he save it from the waves...and itself. This is his story, the story of the hero who fights for all but does it in the shadows. He works in the dark to serve the light.