Starting a colonization
Colonization is only possible through the Pillars. You must send exactly 100 soldiers and 10 scientists to an unoccupied position.
The target must be an unoccupied slot. If another planet, player, or bot already occupies that position, colonization fails.
The 100 soldiers and 10 scientists are consumed when colonization succeeds.
Colony limit, bonuses, and exceeding the limit
You start with your home planet. Your player level unlocks up to 8 additional colonies at level 40. The total can never exceed 13 planets for a new colonization.
Levels 4 / 8 / 12 / 16 / 20 / 24 / 32 / 40 unlock 1 / 2 / 3 / 4 / 5 / 6 / 7 / 8 colonies, respectively. The home planet does not use a colony slot.
If your universe's colony bonus is active, its N slots are added immediately, regardless of your level. The Fragment of the Frontier Throne adds +1 colony only at level 10, and only from player level 20 onward. Its levels 0 to 9 add no slots.
The total capacity is min(13, 1 home planet + level-based colonies + active universe bonus + applicable artifact bonus). If your empire exceeds a lowered limit, you keep all your planets and they continue to function; you can no longer colonize while the limit is met or exceeded.
Example
At player level 40, without a universe bonus or artifact, you can own 9 planets: your home planet and 8 colonies.
With an active universe bonus of 3 slots, you can reach 12 planets. With the Fragment at level 10, you can reach 13 planets. This example does not mean the bonus is active in your universe.
Abandoning a colony
Abandoning a colony starts a delay of 1 hour; it is not immediate.
The home planet cannot be abandoned.
Some situations also block abandonment, for example if a linked fleet is still active.
During this countdown, you can still return to the colony and view its screens until the delay ends.