The Hidden Fortress
It's not a game for Sam. He goes to the Crystal Worlds to work, digging for teleport stones that he sells to adventurers.
Then he finds a stone with no destination marked on it, just a serial number. On a whim he decides to teleport - and he finds himself in the underground vault of a rogue programmer.
Now, equipped with tools no gamer should have - tools he doesn't know how to use - Sam returns to the game. There is no sign of the programmer, for one simple reason. The programmer is in hiding, hunted by a mysterious group of assassins. Now Sam has drawn the attention of the hunters. They chase him through the Crystal Worlds, and when he logs out, his friends IRL tell him that men in dark suits have been asking about him ...