Sworn enemy.

It is this racial ability that makes elves powerful Chaos faction players. And in 3.0, new druids also increase the hero's spell power while they are alive. Of course, they usually live longer than sworn enemies, especially with an upgraded empathy skill and sufficient mana.

This ability has 2 weaknesses:
1. You need to find the right neutral creatures.
2. The need to return to the castle to add them to the list of sworn enemies.