Colonized planets form the backbone of your empire and a successful campaign will usually require the player to take and hold at least a few habitable planets in addition to their starting homeworld.
The screenshot above shows Mars, an uncolonized planet in the Sol system.
How to colonize a planet
To colonize a planet, the player needs to build a Colony Ship from a Shipyard and then launch it with a Citizen to staff it. The Boarding dialogue will appear when the Colony Ship is first created at the Shipyard, but if the player is not ready to launch it yet, the dialogue can be cancelled and it will be reactivated once the player manually selects the Colony Ship from the Shipyard and moves it to an adjacent hex.
The Colony Ship is then either manually guided to the waiting planet, or the player can use the Auto Colonize button to allow the game to choose a suitable colonization target instead. Once the Colony Ship reaches itâ€™s target, the Colonist will colonize the planet, which the player can then rename if they so wish.
Colony ships can only colonize target planets that suit the species of Citizen on board, and are restricted from colonizing the more extreme planet types until certain colonization technologies are researched later in the game. For example, Humans cannot naturally colonize Radioactive worlds and would require the Extreme Colonization technology to settle on. However, the Cosmic Contaminant can naturally colonize such dangerous worlds without the equipment gained from Extreme Colonization.
Types of Colonized Planet
In Galactic Civilizations IV: Supernova, Colonized planets fall into two categories: Colonies and Core Worlds, and it is important to understand the difference between the two.
Colonies are created when a player first lands a manned Colony Ship onto a habitable planet with a Class of 1 or more. They will be populated by the single Citizen that originally staffed the Colony Ship and that population will not increase. They also have a Resource Input score each for Minerals, Technology, Wealth, Farming and Culture. The Colony will contribute its Resource Output, subject to a distance based Decay penalty, to the Planetary Input of the closest Core World, and is considered to be attached to that Core World. Players can build Orbital Improvements to Colonies but otherwise they cannot be manually developed in any other way.
Core Worlds are created when a player assigns a Governor to a Colony that has a Class level of 10 or more, opening it up to manual development. The Core World has its own Resource Input as usual, but any attached Colonies will also contribute a portion of their Resource Input scores, modified by Decay. In the screenshot above, note the six attached Colonies which are providing a very large boost to Planetary Input.
Alongside Orbital Improvements, the player can now build Districts and Improvements on the planet, and the Population will grow, periodically spawning new Citizens according to the Growth rate of the planet.
Picking the right Colonist for the job
The statistics of the Citizen best suited for the Colony Ship will depend upon whether the target planet is intended as a Colony or a Core World too: for a Core World itâ€™s advised to pick a Colonist with a low Expectations score, to keep Approval penalties to a minimum. Colonies that are not intended to be developed are fine to dump off poor quality Citizens, particularly those with high Expectations scores, who might be quite troublesome on a Core World.
Planets with a Class higher than 1 may be colonized, with Core Worlds requiring a Class of at least 10. The higher the Class of planet, the better the Resource Input will be, and the more tiles will be available for development.