Fire Emblem Gaiden is a role-playing game developed for the Nintendo Entertainment System. Set on the continent of Valencia, the story unfolds in two rival territories: the northern Kingdom of Rigel and the southern Kingdom of Sofia. As Rigel invades Sofia, two heroes, Alm and Celica, unite to lead an army against Rigel and the Dark God Doma, striving to restore peace and uphold the Earth Goddess Mila's tenets.
The Continent of Valencia is split into two territories. To the north is the Kingdom of Rigel, home to followers of the Dark God Doma. To the south is the Kingdom of Sofia, where the Earth Goddess Mila is worshipped. When Rigel invades Sofia, two heroes, Arum and Cellica, raise an army to topple Rigel and the Dark God that is backing the conflict.