Players each assume control of two survivors. These constitute the crew of the ship’s shuttle when it returns to the Riga, having broken camp on the surface of the alien world. The final week-long expedition to the surface is finished. It is time to head for home.
When the shuttle approaches the Riga, something is badly wrong. The ship does not respond to hails. Fires flicker in some of the Riga’s windows. The computer gives a garbled account of a battle against an unidentified threat. It is a battle the crew appear to be losing.
As your survivors explore the Riga, you will learn more about what happened. You will discover firsthand the nature and danger of the Threat. While this sinister menace may be beaten back, you lack the means to defeat it. Your only hope is to evacuate before it overwhelms you. In order to do this you will need to refuel the shuttle.
You must load the shuttle with a fuel mixture rich enough to reach safety, but there is more. Your safety depends not only on reaching an outpost of the Earthly Imperium, but surviving the aftermath. Humanity, presided over by an autocratic and capricious aristocracy, is the greasiest pole imaginable. Scapegoats are inevitable. You can guard against this in various ways; by rescuing more survivors, performing heroic deeds, achieving secret objectives or collecting evidence with which to blackmail your superiors.
There is the Riga to think of too. A terrific battle has raged inside the ship and it is badly damaged. You will have to contend with fuel leaks, fires, toxic fumes and worse. Affecting all of this is the Zeno Effect. The alien threat is no straightforward monstrosity. It’s presence seems to subtly alter the fabric of reality. On the Riga, the unwatched pot always boils.
When the shuttle is launched, players win the game if they meet or exceed their evacuation target. In a game of ordinary difficulty, this starts at 9, meaning that each faction must evacuate 9 survivors to win. However, each success scored in the game reduces your evacuation target by one. Successes can be scored in many ways; by completing missions, solving crisis steps and/or having certain items equipped to an evacuating survivor.
If you have the highest evacuation target when the game ends, you automatically win if all the other players win. So if you find yourself dropping behind the other players, you can still win by focusing on helping them to prevail. Your survivors may never see Earth again, but somewhere among the stars, some day, statues will be erected to them. Small consolation perhaps, but it is something.
The game is lost when a critical token cannot be placed or a critical card cannot be drawn. The former means the ship has sustained too much damage. The latter means time has run out. Failing to resolve a crisis can end the game suddenly and spectacularly. Ignore collision warnings, reactor sirens and incoming missile alerts at your peril.
The shuttle can be launched as soon as it is ready. The quicker you transfer fuel, coolant and plasma to the shuttle, the sooner this will occur. If you have more crew, the shuttle can be more effectively operated. Adding survivors to the shuttle reduces the amount of fuel, coolant and/or plasma you need.
When the engines are ready, any player with a survivor aboard may initialize the launch sequence in their turn, as long as they meet their evacuation target. Once begun, the launch sequence cannot be aborted: the shuttle automatically launches the next time any player plays a scene card featuring a launch icon.
This means that the game is not merely a race against time, but a race against the other players. If another player has achieved their evacuation target and is rushing for the shuttle.. well, you might just have to slow them down! So it is probably in their interests to voluntarily slow down and help you.
Not that launching the shuttle is quite the end. Unscrupulous survivors may have stashed things aboard that pose a threat to your escape. Radioactive fuel rods fetch a high price on the black market. As, of course, do the eggs of parasitic alien lifeforms unknown to Imperial science.
As a player, your turns are spent performing actions and resolving scenes.
Actions are the things your survivors do, such as moving, operating ship consoles, carrying out repairs and searching. Most actions have a predictable outcome. You gain actions at the start of your turn by declaring haste. This is simply the number of actions you want to take; between 0 and 9. If you choose more haste will gain more actions. However, haste equates with noise and carelessness, making it difficult to hide from the Threat and potentially altering the outcomes of scenes.
Scenes are brief narrative interludes. They are triggered when (but not only when) a survivor explores an unexplored part of the ship. When a scene is triggered, the other players inspect their hands and may (or must!) play an eligible card. It is then resolved. A scene can be almost anything and it will almost always have two possible outcomes. Which outcome applies depends on the decisions you make, or have already made. Vitally, those decisions are made in ignorance of the card. Something moves in the darkness. Do you shoot? It could be the threat. It could be a loose fuel cylinder! How to know? You must read the signs. The board, the player, the number of cards in his hand, would he really do that to you?..