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The landscape of Chiron is alien, yet familiar, with terrain properties and productivity determining square productivity. The exact values of a square determines its bare yields (nutrients, minerals, and energy), and yields with improvements.

Overriders[ | ]

Certain features completely ignore rainfall and rockiness modifiers, so they're important to get out of the way first. Yields are in the format of nutrients/minerals/energy.

  • Monolith: 2/2/2 yields. This is the best possible yield combination initially.
  • Forest: 1/2/1 yields initially.
  • Xenofungus: No yields initially (1 nutrient for Gaians).

Rainfall[ | ]

SMAX Rainfall

Rainfall patterns are heavily affected by mountains: Western slopes will carry more rainfall and be more fertile.

Rainfall level determines a land square's base yield of nutrients (all are +1 with a farm).

  • Arid: 0 nutrients. Early on, these will usually be best served by planting forests (mine and farm won't surpass forest yield).
  • Moderate rainfall: 1 nutrient.
  • Rainy: 2 nutrients. Note that until Gene Splicing is researched nutrient yields will be capped to 2, so a farm is only useful for offsetting a mine's -1 nutrient.


  • Rainfall is generally higher in coastal and tropical regions.
  • Due to Planet's eastward winds, mountains raise rainfall westward and decrease it eastward. Changing terrain elevation can thus be used to your advantage, making mountains to your east or your enemy's west.
  • Rainfall is a level higher on river tiles.

Rockiness[ | ]

SMAX Rockiness

A rocky peak. The amount of brown stone provides a visual indicator of the potential of an area.

Rockiness level primarily determines a land square's mineral production potential.

  • Flat: 0 minerals, 1 with a mine.
  • Rolling: 1 mineral, 2 with a mine.
  • Rocky: 1 mineral, 3 with a mine (4 with a road as well). Disallows farm and forest. Provides modest defense bonus to units, and costs double moves to enter. Note that until Ecological Engineering is researched, mineral yields are capped to 2, making these squares not very useful.

Altitude[ | ]

SMAX Altidue

A small mountain range. A base perched near the peak will benefit from excellent solar generation.

Altitude of a land square affects the potential energy collected by a Solar Collector.

  • <1000m above sea level: 1 energy. Note that this matches a forest's energy yield.
  • 1000m-2000m: 2 energy.
  • 2000m-3000m: 3 energy.
  • >3000m: 4 energy.

Note that until Environmental Economics is researched, yields will be capped to 2 energy.

Rivers[ | ]

SMAX River

A typical river. Coupled with its placement on the western slope of the mountain, it's an excellent spot for a farming base.

Rivers flow typically from the source to a larger aquatic body (an inland lake or the open sea) and have multiple effects making them very useful.

  • +1 rainfall. Note that you can create rivers, so this is a way to make areas more farmable.
  • +1 energy.
  • Act as a road for movement.

Ocean[ | ]

Ocean squares are much simpler, unaffected by all the above. They are generally not as productive, due to focusing on only one yield.

Landmarks and Resource Bonuses[ | ]

Separately from other effects (and thus able to combine with them for very good squares) are the effects of landmarks and resource bonuses. A resource bonus applies +2 of the resource, and bypasses tech limitations for the resource, making them excellent locations to build improvements. Landmarks have specific effects, though mostly just +1 to a resource: