The Nexus Mirror by N.E. Michael

Ever since his father’s mysterious murder, Raiden has been having visions of beings with extraordinary powers which he sketched into comics. The man responsible for the murder, billionaire Jimmy Roko, controls the world from his lofty, impenetrable Silver Tower. Compared to Roko’s vast army of robotic creatures and soldiers, Raiden is helpless. At least he was, until the epic heroes from his comics came knocking at his doorstep…

Forced away from everything he’d ever known, Raiden is thrown into a war filled with mystical beasts and terrible demons, super-powered heroes and futuristic battle-drones, ancient portals and daring new worlds. The fate of the universe rests in Raiden’s hands as he fights against Jimmy Roko and the Chief of Shadows to protect a young girl named Sarah, the last surviving Surger, who possesses the key to the ultimate weapon.