"Sword of Spirits" is an exciting science fiction book written by John Kristoff. The book tells about the war between two factions of humanity - technocrats and feudal lords in a post-apocalyptic world. The main character, a young warrior, embarks on a dangerous journey to find the legendary Spirit Sword, which, according to legend, should change the course of the war and bring peace. The author successfully combines a dynamic battle scene, complex moral dilemmas and philosophical reflections in the book. This is an exciting adventure that will leave behind many important considerations.