Ares Expedition: Crisis is a new expansion that uses the mechanics of the original game, Terraforming Mars: Ares Expedition, in a new, challenging way. Play alone or team up with up to three friends to save Martian society after a catastrophic collision with an asteroid that destroys nearly all infrastructure.

In Crisis Mode, the planet has already been terraformed, but the lingering effects of the collision are lowering temperatures, reducing oxygen levels, and freezing the oceans. Worse still, there is no time to evacuate the entire population. You must act quickly, implement projects to counter the immediate crises and reterraform the planet before it becomes uninhabitable... with billions of people still on it.