Interior Skills

Interior skills can be researched at the Natural Institute.

Resources

 * Planting : +5% Food yield for all your cities.
 * Food Skill : +2% chance of getting Flooding Plains when Terraforming to Plains.
 * Digging : +5% Sand Stone yield for all your cities.
 * Geology : +2% chance of getting Deep Lake when Terraforming to Lake.
 * Smelting : +5% Metal yield for all your cities.
 * Metalurgy : +2% chance to get Mine Mount when Terraforming to Mountain.
 * Lumbering : +5% Wood yield for all your cities.
 * Woodcutting : +2% chance to get Dense Forest when Terraforming to Woods.
 * Extraction : +5% Crystal yield for all your cities.
 * Gemology : +2% chance to get Crystal Desert when Terraforming to Desert.

Production

 * Forging : -5% Metal material required for Weapons produced in the Arsenal. lvl 8: 169 SP. lvl 9: 332 SP lvl 10: 613 SP
 * Weapon Theory : -5% Weapon production time in the Arsenal.
 * Craft : -5% Wood material required for Frames in the Carpenter's Workshop.
 * Airship Theory : -5% Frame production time in the Carpenter's Workshop.
 * Magic Transfer : -5% Crystal material required for engines in the Energy Workshop.
 * Dynamics : -5% Engine production time in the Energy Workshop.