Total Immersion: Dark World by S.J. Larsson

Sid Vicious thought that when he defeated the player-hunter, The Seeker, after eleven months of planning, he’d saved all the players of Elora Online from the Dragonbane Killer’s wrath of killing and looting. When he’s thrown into Dark World, a secret part of Elora Online where his name changes to Sid, his race to being a Nuudle, and his class the ever-elusive Mystic, he’s stunned that he can physically feel the game around him, and he can’t access the real world or Elora any longer. He’s trapped.

As he uncovers the mysteries of Dark World while being stalked by The Seeker, his old nemesis who also now has a new race and class, he makes unusual friends who help him claim his summons for Mystic. With each summon he wins in impossible battles, he gains more power, and unlocks the secrets of what Dark World really is…what Elora Online is, and why he’s there. The hits make him bleed, and the deaths are painful. He must defeat Seeker once again, and this time it’ll take more than a year of planning. It’ll take a worldwide war.