Religious takeover

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Religious takeover is the method by which missionaries can take over cities and planets in the civilization stage and in a way, the space stage. To begin the process to start an religious takeover, the player must start a convert attempt with the targeted city or solar system.

[edit] Civilization Stage

First, the player must have Religious city, or religious vehicles. Then, they must send the religious vehicles to a computer controlled city. Remember that the more religious vehicles that you have going to one city, the faster the takeover will progress. Once the religious takeover bar is full, they will decide to convert to your religion, and will join your nation.

[edit] Space Stage

If your archetype is Zealot, you can use your Fanatical Frenzy ability to convert the aliens to your empire, but it seems more like replacing the aliens with your own creature.