Alien invaders

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It has been confirmed that you will be able to invade other civilizations at their Civilization phase, and that you will not be invaded by aliens during your Civilization phase.

This can only be done using the UFO. To begin with, you will only have simple weapons to attack other civilizations with, but later you will gain access to better weapons and will therefore find it easier to destroy others.

In one of the demonstration videos, Will Wright ends up attacking a colony of a species, leaves, and receives a message from the rest of the species. Although the actual details of the message are not clear, Will Wright goes on to explain that the other species are now moving to attack Will Wright’s creature’s planet, while Wright's creatures call out for help from him. In one demonstration video during the Creature phase Will Wright notes that the game will always try to balance out the food chain, creating creatures above you, so it seems that constant hostility will not always be the best option and care must be taken when interacting with other planets. After reviewing the message, It said the following: "Greetings! We Greevils will repay your aggression! You better rush home to defend YOUR homeworld!" Apparently, The people he attacked earlier by zapping, throwing, abducting, and drowning Greevils didn't go over so well.