Obsidian! (The Deathstones Trilogy) (Volume 1)

For three best friends the beginning of junior high turns into a perilous adventure as they fall through a mysterious portal and set out to seek their true destinies in a fantastical land ruled over by a pantheon of Greek, Roman and Norse gods. Blake, Henry, and Garret take turns documenting their surreal experiences as they learn about the prophesy that bequeaths them with the powers and weapons of a warrior, sorcerer, and a changeling. They will need to dig deep into their own strengths in order to save a world riddled with capricious deities and startling revelations.