The Sundering - The Sundering, #1

Two queens. Two worlds. One war impending between them. In a realm perpetually Light, a portal is hidden from those of mankind. Sebastian of Zelal, the Queen Regent's Assassin, always believed the stories were a lie. He's about to find out for certain. After given the mission to find the portal, he must wander into lands unknown, unsure if he will live or die. Who are the Ancients, and what will happen to all mankind should they arrive? He hopes never to find out.
Time is ticking. The second gate is waiting to open, with fiendish powers and monstrous things fighting him along the way. Goddess forbid the two queens should be allowed to win. Light unto darkness, and darkness unto light. for what is mortal man against a force as old as humanity?