AI War:Planet Mark
AI planets have a Mark level, similar to the Mark of units.
A planet's mark is displayed on the galaxy view, left to its planet. MkI and MkII are not displayed. MkIII to MkV are displayed with the same colors as the unit's mark: white with dark red outline for MkIII, with a bright red outline for MkIV and bright purple outline for MkV.
An AI with a high Difficulty will have more planets of higher mark. Inversely, an AI with a low difficulty will have mostly low mark planets.