Lost Empire: Immortals is a 4x turn-based strategy game, featuring multiple star maps with up to 5000 star systems, 6 different races and an extensive research tree. The battles are rendered in 3D - although the player cannot control them - and the final objectives can be domination, diplomacy, research or exploration.

The story begins with the Eonians, a long lost civilization which has given the knowledge of navigating the stars to the other races (the Horde, the Alkiths, the Megalanians, the CrystalSpirits, the Tritons and the Humans). When the Eonians disappeared, so did their technology, but it was soon rediscovered, exploring and expanding becoming possible once again.