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Mapcraft - Fantasy map designer

WorldGen - SciFi universe generator

Mapcraft Web - Web based fantasy map designer

All code for the project is released under the GPL, and is copyright Samuel Penn.

The text on this wiki is dual licensed CC-BY-SA and GPL.

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MesoGaian worlds are in the second stage of the life, after EoGaian, being between 500 million and 2 billion years old. With stable weather systems, erosion and techtonics beginning to kick in a cycle that removes carbon dioxide from the atmosphere. These worlds are not habitable, but may be a source of raw material for food if nothing better is available. Life, if it exists, will most probably consist of single celled bacteria.

Many worlds reach a MesoGaian stage, but then never reach the full Gaian type.

If the world is too hot, either due to too much carbon dioxide or being too close to its star, then it may undergo a runaway greenhouse effect and become a Cytherean world.

If the world is too cold, it can become a GaianTundral.

If the world is too small to retain an atmosphere, it can become an Arean world (such worlds are normally classed as EoArean to begin with, but there isn't always a well defined line between the two).

If everything is perfect though, it goes on to become an ArchaeoGaian world, as life begins to dominate the processes which control the atmosphere and the nature of the planetary surface.


Many MesoGaian worlds have some form of life, but not all. Mostly, they will be single celled bacteria unless evolution has been particularly quick. Distribution may be as follows.

2d6 Life level
2-4 None
5-6 Organic
7-12 Archaean
pcl/mesogaian.txt · Last modified: 2015/02/04 22:39 (external edit)