look for the line.
there you will immediately find the coefficients for increasing and decreasing blood rage.
then the bonuses:
CREATURE_GOBLIN
DEMON_RAGE_BONUS_HEALTH
1
0
DEMON_RAGE_BONUS_DISABLE_ABILITY
0
0
ABILITY_TREACHERY
DEMON_RAGE_BONUS_DEFENCE
3
0
DEMON_RAGE_BONUS_DISABLE_ABILITY
0
0
DEMON_RAGE_BONUS_ABILITY
0
0
ABILITY_NO_ENEMY_RETALIATION
I made unique bonuses for my cultists, but in the end, I gave up because the feedback was too varied; I just set bonuses to attack, defense, and courage.
Added 1 minute ago
The "boiling blood" ability is useless; it doesn't affect the bonuses.
Wyverns don't have blood rage because that's how the game is programmed