The Last Horizon. The Chronicles of Talahm, #4

Die to save the universe, or die with it. Confronted with a horrible truth kept secret for centuries, Seventh Sorceress Emma Artair has no choice. She can only save the world by sacrificing herself, but accepting it isn't easy. and neither is her final journey. To reach the swimming stars beneath Skypoint, The Sea Wolf must sail through waters fraught with danger and the bloody consequences of Emma freeing the Nephilim.
As the last horizon looms, Emma and her friends face deception, possessions, betrayal, death, and thousands of rogue portals-each obstacle dashing hope and cinching Emma's fate. With secret bloodlines, an imprisoned king, and a demon working against them, the heroes face their hardest battle yet: make it to Skypoint before the Nephilim overrun the world, before the black hole consumes Langoth, and before Emma loses her nerve.
After all, how does one walk into eternity's arms?