Joe LaRue of The Koalition writes: Warhammer 40,000: Age of Sigmar is an expansion of the Warhammer Game shop that came out about 6 years ago to expand on the vast fantasy world that they already had running. This new change replaced the Old World medieval-style feel of the game with a new and exciting multi-dimensional Mortal Realms. This also in turn introduced players to new factions and new play styles. For some players, it was a kick in the face to have this new world brought forward, but for others, it meant starting over from scratch and learning all over again.

Source: N4G PC Warhammer Age of Sigmar: Storm Ground Review – A New Way to go to War I The Koalition