While in the battle, you can tap and hold the Buff icon and read what it does.
Here are the heroes who can apply this buff:
- Robin Bad (Passive Ability)
- Mara (Ability 3)
- Solius (Leadership Ability )
- Rantha (Ability 2)
- Tromgar (Ability 2)
- Rin the Unseen (Ability 3)
- Master Duo (Ability 3)
- Kang Xi (Passive Ability )
- Yogi (Passive Ability )
- Grock (Passive Ability)
- Victoria (Ability 3)
- Titania (Ability 3)
- Ace & Sin (Passive Ability)
- Kaira (Ability 3)
- Buff (Ability 2 - one of the possible positive effects)