Crystals of Arborea was published by Silmarils in 1991. It precedes Ishar both chronologically and by its gameplay. Morgoth, the main antagonist of Crystals of Arborea, is the father of Krogh, the one of Ishar: Legend of the Fortress. Moreover, most of the heroes of the game, Jarel's companions, can be met in Ishar or even in Ishar 2.
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