The FIDSI are the five primary resources in Endless Legend:
- Food - Used to grow the population of your cities.
- Industry - Used to build City Improvements, Expansions, and Units in your cities.
- Dust - The game's currency, allowing you to buyout production, buy and sell goods, units, and heroes on the Marketplace, bribe villages, trade with other empires, and more.
- Science - Used to unlock new Technology over time.
- Influence - Used to establish an Empire Plan as well as negotiate with other Empires.
FIDSI output describes the amount of each resource produced every turn by a tile or city. A tile's FIDSI output is the output of its base terrain modified by the presence of an anomaly, river, or strategic or luxury resource. A city's FIDSI output is the sum of the output of all controlled tiles combined with and adjusted by the output and maintenance of all existing city improvements and population units.
The base production for any of the five FIDSI resources is the sum of all of that resource produced by city improvements, tiles, and . The modifiers (whether per-city or per-empire) do not compound; instead, they are all summed up and then applied to the base production.
For example, in a happy city during summer, with the Founder's Memorial, Public Granary and Seed Storage built with a Spice booster active, the calculation to determine how much food the city is producing is as follows:
This same calculation process applies to all FIDSI resources, as well as most other things in Endless Legend, such as unit attributes.