Null-Magic - Prevents the next buff applied to this Hero. Lasts until consumed, can't be cleansed.
Type: debuff - Category: Status Effect, Stack
See also: | 
Back Splashed | 
Magic Prism | 
Null-Magic | 
Observation | 
Spirit Linked | 
Wildfire
Null-Magic can prevent any Buff, even non-purgeable buffs. Once Null-Magic is applied it blocks/prevents a new buff to be added to the hero, but it does not remove an existing buff.
When multiple buffs are added, such as from Runes at the beginning of battle, Null-Magic prevents a random Buff. If the Buff is a stack for example 3 
Foresight from Runes or 2 
Command, the entire stack will be prevented. This is considered a bug.
Because Null-Magic is added right at the start of the battle, it can also directly prevent 
Oak Form, 
Graniteform, 
Shrouded, etc.
Last but not least, Null-Magic ignores any form of debuff immunity.
Heroes
The following heroes have or can inflict/apply Null-Magic:
Void Aura (Trait): All enemies start with a stack of Null-Magic, and gain a stack of it once per turn.
Null-Magic Technique (Trait): Other Assassin allies have a chance to apply Null-Magic on a basic attack, a status that prevents the next buff added.
Spell Rend (Special Attack): Melee Physical attack on target enemy. Transfers 1 Debuff, and adds Null-Magic to the enemy.
Immunity
There is no known immunity.