Asynchronous Multiplayer Mobile Gaming: "Aurora Feint II accomplishes this through the use of 'ghosts'. A human player builds up a character in the game world that has the ability to act autonomously while the player is offline. The player's ghost can be challenged in the game world at any time, and when the player returns to the game world, the ghost can be controlled directly. It's a novel approach and solves a number of problems with people wanting to play with their friends on their own schedules.
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