A basic simulation of a planet that can be simulated from its beginnings as a lifeless rock, or from a later point in time.
The game includes 8 (eight) different planet archetypes. They are: Random Planet (random features), Aquarium (water planet), Stag Nation (stone age civilization), Cambrian Era Earth (550 million years ago Earth), Modern Earth (1990's Earth), Mars (a terraforming challenge), Venus (another terraforming challenge), and DaisyWorld (Gaia hypothesis exploration).
The game can be played in four different modes with different difficulties and "energy levels" (a form of currency for your interaction with the planet). They are: Experimental Mode (infinite energy), Easy Game (5000 energy), Average Game (2000 energy), and Hard Game (2000 energy and unregulated Gaia, which seems to mean that the world will be relatively chaotic).
There are filters so that you can look at or block view of: Oceans, Biomes, Cities, Life forms, Events, Landmass temperature, Rainfall, Winds, Ocean currents, and Ocean temperature.
You can display graphs of the global air sample, biomes by population, life forms by population, and technological levels.
You can manipulate "models," which control how the planet tends to function. They are the Geosphere, Atmosphere, Biosphere, and Civilization.
Civilizations can be based on any animal, except single-celled. Thus, a whale civilization, or a dinosaur civilization are entirely possible.