There are 4 types of effects in battle which are presented in blue, yellow, red and green colour.
Blue Buffs are unique negative or positive effects that are special for a spesific heroes. They cannot be dispelled.
Green Buffs are common positive battle effects that a lot of different heroes possess. They can be dispelled.
Taunt is a yellow positive battle effect. It is also unique to Defender heroes. It cannot be dispelled.
Debuffs are negative battle effects that are coloured red, and can also be dispelled.
Black Debuff is a unique negative battle effect that could be only met in guild raid "The Depths of Black Machinery". It can not be dispelled.
A Debuff is a negative battle effect a hero have and can apply to heroes on the opposing team. There are various types of debuffs such as Poison, Daze or Armour Decrease. Casting debuffs might come in handy in the battles, and can decide the outcome of it. Or, on the contrary, become a signifficant challenge in the quest to reclaim victory.
While in battle, you can tap and hold the Debuff icon and read what it does.
There are a lot of various debuffs in the game. Most of them are pretty common, and some are unique for a certain race or even hero. Here is a full list of debuffs:
