Gastark is a country which lies to the north of Roland, and is ruled by King Refal Edia. Like all the countries, Gastark has its own unique magic, including a powerful destructive magic spell which is evoked with the incantation, "From the West, the empty, the formation, the yang, I bring forth brilliance!"
Although Gastark is quite a small country, it starts to conquer many of the surrounding, more powerful nations in the middle of the anime using the power of Refal's sacred sword, Glouvil. Sui and Kuu's mission in traveling around the continent is to collect Hero Relics and bring them back to assist Gastark in the invasion of neighboring countries. Refal reveals to Kiefer on their first meeting that the reason he is conquering other countries is to become King of the entire continent in order to create world where everyone can live peacefully, which is very similar (in theory) to Sion's goal.