Patrick Hodges 
Endgame [EPUB ebook] 

Go to Mount Calabur. Stand on the Nexus. Win the game.
Eons ago, a game to determine galactic dominance began. Now, on the distant world of Elystra, that game is reaching its conclusion.
Two mighty armies clash: on one side, Elzaria the Lightning-Wielder, backed by her brother’s army, is poised to claim the third Stone and final victory. On the other, Earth pilot Maeve and her allies are all that stands in her way.
With the fate of the entire galaxy at stake, who will make the ultimate sacrifice?