PureSim Baseball 2007 is a text-based computer baseball simulation published by Matrix Games. Originally developed by independent game developer Shaun Sullivan, the first Matrix version was published as PureSim 2005 on 5 October 2005.PureSim allows creation of a fantasy baseball world made up of either fictional players or real major league players imported from the Lahman Database. Leagues, called "associations" in PureSim, can be set up with as few as two teams to as many as fifty.