Board Thread:Warhammer 40k General Discussion/@comment-25101690-20160717141803

Is anything known about criteria for building new forge worlds? What would make a good forge world, size, rich natural resources, or just an already well developed industrial world?

What about hive worlds? I would expect the main criterion is a good environment, clean air, fertile land. But the air will quickly become polluted by the industry of a hive world and the land is never enough to feed the billions of humans.

I guess new worlds are colonised when they have conditions that allow humans to survive: breathable air, clean water, not too many dangerous animals or toxic substances. But on the other side, there are tools to terraform a planet to get these conditions. What could be reasons to take up the hard work of terraforming and which worlds would be chosen for it? 