Talk:Trial:005/@comment-74.213.97.58-20150513155715/@comment-108.54.206.186-20150514010832

It disables the leader skill's effect on specific units. Assuming you have Tridon Leading, and a unit that has 13000 health, a Nullify Leader Skill debuff on that unit will reduce it's health back down to 10000. Leader getting affected doesn't have anything to do with it.