The Blade of Revelation (Book 5 of The Menocht Loop Series)

Ian must pull off the impossible. Achemiss is a thousand-year-old necromancer with potent shadow magic and a trove of artifacts. To save his world and honor his deal with Karanos, Ian has one task. Assassinate him. With Maria, Karanos, and the ever-charming Crystal at his side, Ian seeks out artifacts to level the playing field. He explores treacherous planes and participates in a trial run by the white faction. Hell learn that the upper limit on power is far greater than he thought.