Alien Legacy is an intriguing space strategy game designed by Joe Ybarra, who also designed the famous Starflight series. It's an excellent mix of resource management, exploration, and colony building, all wrapped in an involving, well-thought-out plot.
In 2043, humanity made first contact with an alien - and, unfortunately, hostile - civilization, the Centaurians. Faced with this overwhelming threat, humanity banded together under the banner of the United Nations and began pushing ahead in research to prepare for the coming interstellar war. One of the fruits of this research was the Bussard ramjet, which allowed ships to travel at relativistic speeds and reach the stars in a matter of decades.
In addition to the warships built by the United Nations, humanity also constructed seedships, interstellar arks carrying cryogenically frozen colonists to distant star systems, to spread the seeds of humanity into the stars in case the Centaurians conquered Earth. In 2119, the seedship UNS Calypso was launched to the distant Beta Caeli star system. A few years later, in 2135, the UNS Tantalus was launched towards the same destination. The Tantalus was much faster and was destined to reach Beta Caeli 21 years before the older Calypso.
You play as the captain of UNS Calypso. Arriving in the Beta Caeli system, you expect to find thriving colonies founded by the Tantalus' colonists. But something has gone horribly wrong, and no sign of any active colonies can be found. Your task is to colonize the Beta Caeli system, discover the fate of the Tantalus colonies, and avoid sharing that fate. You start the game with the Calypso, a few faster and smaller interplanetary spacecraft, some resources, and a bunch of robots and colonists at your disposal; more colonists will be awakened from cryo-sleep as the game progresses.
The scope of the game is vast: there are eight planets, four moons, and sixteen asteroids to explore and settle, each with an enormous number of sectors you can search and often mine for energy, minerals or scientific findings. Using the planetary map, you can scan the world for useful resources (and later on for other items). You can then enter any sector with a vehicle, in a "flight sim" 3rd-person view, flying over the terrain and looking for interesting materials to collect. Vehicles can also be used to set up colonies and space stations, as well as to probe more distant worlds.
Once you establish colonies, you can build various installations in them in a manner similar to SimCity, ranging from factories to research laboratories. Their construction and operation requires resources – energy, minerals, robots, and humans. Some of these would have to be brought in advance from the Calypso or an older colony; later, when the colony is properly set up, it will produce resources on its own.
You can also research various technologies using the Tech Manager. As the game progresses and you discover more artifacts, new research projects will become available. Research requires time and science resources, which can either be produced by laboratories in your colonies or collected from planetary surfaces. New technologies range from improvements to existing vehicles or buildings, through new scanners, to altogether new building types.
As the game progresses and you explore and colonize the Beta Caeli system, the plot is advanced through events presented to you by your advisors. During the game, you will have to face and solve various crises in order to avoid the fate that has befallen UNS Tantalus. The game is quite long, giving you hours upon hours of enjoyable play and revealing a rich, complex, and well-written sci-fi plot. Once you complete the game, you will be given a score for your performance, allowing for some replayability by trying to improve on your score in later games.
The only weak point of Alien Legacy is that combat can be controlled only at the strategic level. Once you reach a point in the plot where you are beset by enemies, you can decide where to station your vehicles and how to arm them, but the actual combat resolution is automatic. You can, however, directly attack ground targets, which becomes useful as the plot progresses.
The game's mouse-driven interface is very comfortable. The sound is also quite good, with nice background music and various sound effects. Together, the sound and graphics very well convey the mysterious atmosphere of the Beta Caeli star system.
All in all, this is a very good strategy/exploration game with an excellent plot, a true gem which should give you many hours of enjoyable gameplay.