City size limits

 No city without Basic Infrastructure can grow bigger than size 2. For cities with Basic Infrastructure, planet's radiation limits how big they can grow. This limit can be increased by researching Radiation Resistance, Strong Resistance and Mental Powers technologies and by building Radiation Resistor and Skyscraper buildings or Protector wonder. Cities on Alien Forest or Radiating Rocks tiles have lower size limits than cities placed on other terrains.

Irrigation

 For some reason it's hard to get water to flow long distances in this world. Irrigation is only possible on river tiles and tiles cardinally adjacent to oceanic terrain once Manufacturing technology is known. Water Flow technology allows us to irrigate tiles cardinally adjacent to city centers and river tiles. Once one knows Deep Pumping technology, one can irrigate any tile where terrain type allows it - no need for adjacent tiles to have water.

Unit veterancy

 There is two veterancy levels for units: Regular and Elite. Regular units are promoted to Elite ones only rarely (10% chance) through real combat experience, and never by doing worker activities. One gets Elite units by building them in a city with Training Facility. Elite units have 100% bonus in combat compared to Regular ones.

Gold upkeep style

Gold upkeep for all buildings and units is paid in a lump sum after all cities have been processed. If the player does not have enough gold, random buildings from random cities are sold. If still more gold is needed, then random units with gold upkeep are disbanded.

Calendar

Game starts at year 250 Galactic Era. Each turn equals one year.

City Radius

 Basic city radius square is 4 meaning that city can work all the tiles adjacent to center and one tile two tiles away in the middle of each side. This means that there is 13 workable tiles. Building Transportation increases radius so that 8 more tiles become available for total of 21.