Gravity

Planets can have 3 different gravity ratings: low, normal, high. A race has tolerance to one gravity rating, and will receive production penalties on planets with a different gravity. The penalty is generally worse if you go higher than your race tolerance than if you go lower (see table below).

The penalty can be counteracted by researching the Gravitic Fields tech and building Gravity Generators on the affected planet.

Note: This does not show up in the research tree.

Production penalty on planet based on race gravity tolerance:

	Low gravity tolerance	Normal gravity tolerance	High gravity tolerance
Low gravity planet	0%	-25%	-25%
Normal gravity planet	-25%	0%	0%
High gravity planet	50%	-50%	0%

A random planet's gravity is a function of its size and mineral richness:

	Tiny	Small	Medium	Large	Huge
Ultra Poor	Low	Low	Low	Normal	Normal
Poor	Low	Low	Normal	Normal	Normal
Abundant	Low	Normal	Normal	Normal	High
Rich	Normal	Normal	Normal	High	High
Ultra Rich	Normal	Normal	High	High	High

Exceptions include the Psilon and Gnolam homeworlds (low gravity instead of normal) and Orion (normal gravity instead of high). Custom races can create other exceptions since planet size, mineral richness, and gravity are traits that can be selected independently.

This means that a race with high gravity tolerance will be able to settle the worlds with the best development potential earlier in the game than the race that have to develop gravity generators first. Inversely, a low-gravity tolerance race will have to settle on the worst worlds (small and poor) or suffer production penalties until they can build gravity generators. Furthermore, statistically, the majority of planets will have normal gravity, while high and low gravity planets will be rare. For these reasons, high-gravity tolerance, allowing to settle without penalty on high and normal gravity worlds, is a strong advantage while low-gravity tolerance is a severe drawback.