- Normal - where human and AI players are on almost equal footings
- Nigh-On Impossible ("NOI") - the level routinely chosen by extremely good players
There are two contexts in which the term is used.
- In a random game you can choose your level of difficulty; the program then sets various factors (the most obvious being cash and the contents of your warehouse - but the Imp1 manual includes "the number of mineral resources likely to be found in your country") to make your experience appropriate in relation to the AI players. On the two easiest levels your capital site is selected by the program; on the others you choose your own.
- Scenario writers can assign presumed levels of difficulty to the various Great Powers in the scenario. (Occasionally a player may wonder what on earth the scenario writer was thinking! Probably the writer adapted another scenario but forgot to change the stated difficulty.)