okay, thanks
It is not used in the C++ code, so this value has no effect?
If "raging barbarian" turned on, are all barbs raging, or just some of them? Because I never saw a 25% ?! Then maybe the BARBARIAN_EXTRA_RAGING_UNIT_SPAWN_CHANCE tells the game how many of the barbs get the combat bonus?
At the moment I can't test it, but I will do in some hours, find out if changing BARBARIAN_EXTRA_RAGING_UNIT_SPAWN_CHANCE does anything and if any of the barbs have 25% combat bonus.
edit: Also thank you Lees for your answer

Are there more values which are only used with raging barbarians?