Well, the Beserker back story typically has roots in Norse mythology. They were said to be warriors who had a special ability to tap into a berserk state. This state was thought to be induced by various means, like consuming certain substances or through intense mental and physical training. Once in this state, they would fight with little regard for their own safety, showing extraordinary strength and ferocity. Their back story might also include tales of their origin, perhaps being descendants of a particular group or having a special blessing or curse that led to their berserk nature.
Guts is purely fictional. It's a concept or character that exists within the realm of imagination and creative storytelling rather than being based on reality.
There could be. Naruto is known for his never - give - up attitude and his journey to become stronger. Guts has his own arduous path filled with battles and self - discovery. A fanfic could be written to show how Naruto's character traits are like Guts', perhaps in how they deal with loss, friendship, and their overarching goals. It would be an interesting read for fans of both.