In the Key of Ether: Books 1 and 2

Two worlds, deeply entwined together spin through the endless void... One, slowly dying; the other vibrant and fairly sparking with life and energy. One steeped in the forgotten magics of ages past; the other locked in an endless struggle for mundane survival. Elder gods and deities from nearby worlds and universes watch helplessly as two entire realities slowly begin to drift farther away, spiraling towards an unknown doom. A mighty hero, is needed... Gods and entities stranger than gods sing out into the void seeking the sage, mage or warrior destined to save two worlds. They got Gary...