Larger planets and moons had multiple "territories" in the higher skill level settings. Territories had a natural population limit based on their ecological fitness for the player's species. As the population grew and started to reach the maximum for any one territory, they would naturally migrate out of a territory into surrounding ones. Over time a single colonization attempt would take over an entire planet. This also allowed a player to take over a single territory on an enemy-colonized planet and attempt to build it up. As the population of that territory rose, the inhabitants would naturally try to emigrate to surrounding territories, fighting "migration wars" if they were already inhabited by the enemy player.