Modifier
Duke
duke_modifier
Duke (modifier ID duke_modifier) is a named modifier in Crusader Kings III. It gives Domain Limit +2, Number of Knights +2, Vassal Limit +20, Tax slot +1, Mercenary Hire Cost +10%, Enemy Scheme Secrecy -10% and 1 more. No add_…_modifier command in common/, events/ or history/ adds it. Patch 1.20.1.2, from game/common/modifiers/00_basic_modifiers.txt.
Effects
Where the game adds it
No add_…_modifier command in common/, events/ or history/ adds it.
Source: game/common/modifiers/00_basic_modifiers.txt (line 74), the English localisation (duke_modifier, duke_modifier_desc) and every add_…_modifier / remove_…_modifier in common/, events/ and history/, Crusader Kings III 1.20.1.2.