At learning level 34, you have an option to begin a hatred of a certain horde. There was always tension between the hordes when they were fighting together, but since the infection, the competition spiralled out of control and you now duel the other hordes to steal their soul-energy. You can channel this hatred to give you increased stats against a single horde you hate the most.
For each 2 levels of this skill, you gain +1 attack and +1 IQ against your chosen horde, up to the maximum of +15 attack and +15 IQ. It makes sense to choose your hatred of the horde which is most popular, so you get the bonus in most of your battles, but this can vary (if one player is constantly beating you and you have no trouble with the most popular horde, you may want to choose otherwise).
The cap can be increased by the Hatred AAC, up to a maximum of 40 instead of 30. With the Hand of Peace relic from the auction house, your opponents horde hatred is ineffective against you.
It is important to note that the horde hatred does not count during championships and cannot be used against the crystal horde either.
Learning Level: 34
Max level: 30