Slow trait ensures that it is the last to attack. Since the Heroes Revamped! change slow Heroes get a permanent +25% attack and +25% health buff. With the release of the Challenge Mode the trait got an additional effect which adds a chance to retaliate against any physical attacker (Revenge attack) but it does not work against Leonidus due to his trait.
Boosted damage vs. Slow Heroes
|Mystical||[25/50/75]% damage bonus vs Slow or Tank heroes depending on the rank of this trait (I-III). Each Ascension of the Hero raises the rank (I/II/III) of this trait.||All casters|
Defense from Slow Revenge
|Flying in the Face||Can't be retaliated against.||Leonidus|
The following Heroes that have the Slow trait.
(*more info can be found on Pontifex Mortis and his reincarnated form.)