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Less Unit XP Required

Units require less combat experience for promotions.

Units start with a base of 3 xp needed x a multiplier of 5, giving 15xp for gaining the first promotion.
This mod changes that multiplier from 5 to 3, giving 9xp for the first promotion.
Every future promotion takes that base from the previous and multiplies it.

Changing this mod:
C:programfiles:steam:steamapps:workshop:content:289070
This is where all your subscribed mods are held.
Click the folders until you find the one with UnitExperience.modinfo and Experience.xml.
Right click and open(edit) the Experience.xml file (notepad or notepad++ will do).
You will see this code ->
<GameData>
<GlobalParameters>
<Update>
<Where Name="EXPERIENCE_NEEDED_FOR_NEXT_LEVEL_MULTIPLIER"/>
<Set Value="3"/>
</Update>
</GlobalParameters>
</GameData>
Simply change the line <Set Value="3"/> to what ever multiplying number you want.
eg <Set Value="10"/>, Save it.