Debuff is a skill that allows to reduce the amount of attack points owned by an enemy unit.
Usually associated with Chaos and Nature race, it causes for incoming damage to be effectively reduced, to the point of being eventually nullified if Debuff is more powerful than the attack of the targeted unit. Should that happen, the zero-ed unit won't be able to attack anymore.
Even if stacked with such a deprecating skill, units can still retrieve their original ATK if hit by Silence.
Debuff units can be classified as One-time Debuffers and Continuous Debuffers, based on the frequency of the skill.
One-time Debuffers
These units can inflict the skill only once (usually when they enter the field).
| Name | Tier | Race | Description |
|---|---|---|---|
| Koschei the Immortal | 
|
Chaos | Debuff all enemies for 1 turn |
| Witch | 
|
Chaos | Permanently debuff all enemies |
| Owl | 
|
Nature | Permanently debuff random enemy |
| Tree | 
|
Chaos | Permanently debuff enemies on line |
| One-Eyed Ogre | 
|
Chaos | Permanently debuff enemies on line |
| All, Prince of Sands |
|
Order | Permanently debuff all enemies on the field when killed |
Continuous Debuffers
These units can inflict the skill more than once, so enemy's units will effectively become weaker and weaker as turns pass.
| Name | Tier | Race | Description |
|---|---|---|---|
| Wise Owl |
|
Nature | Debuffs random enemy at every End of Turn |
| Mother Owl |
|
Nature | AoE Debuff to all enemies at every End of Turn |
| Sporelok |
|
Nature | Grants "Debuff at every new turn" skill to enemies on line |
| The Killer Serpent |
|
Nature | Debuffs melee enemies who appear on the field |
| Dark Tree (Debuff) | Chaos | AoE Debuff to all enemies at every End of Turn | |
| Debuff to random enemy at every End of Turn | |||
| Madam Agony |
|
Chaos | Debuffs enemies who appear on the field for 1 turn depending on how many wounded units are present |
| Flesh Eater |
|
Chaos | Debuff Order enemies for 1 turn at every End of Turn |
| Chuba Cabras |
|
Chaos | Debuff Order enemies for 1 turn when an enemy attacks |
| Fan Dancer |
|
Order | (Debuff random enemy at every attack) |
| Amaterasu, Eternal Sun |
|
Order | Debuff melee enemies at every attack |
| Volcanic Gration | 
|
Chaos | Debuff all enemies for 1 turn every 3 turns |
| Big Booty Judy |
|
Order | Debuffs all enemies every 3 turns |
| Io, Lord of Orgasm |
|
Nature | Debuffs all enemies every 3 turns |
Set ATK
A particular type of Debuff, Set ATK allows for a unit to temporarily or permanently overwrite the standard ATK value of other ones, and forcefully imposing a new value. Click here to continue reading...
Toxin
A particular type of Debuff, Toxin allows for a unit to reduce the standard ATK value of other ones, and forcefully imposing a new value. Main difference is that this reduction is percentage-based, and not static. Click here to continue reading...
Comparison with other skills
Debuff vs. Steal
Pretty much like Debuff, Steal is another skill that can be found on Chaos units and allows to lower the offensive power of an enemy.
Differently from that, it can be found also on Nature units, it does't boost the attacker's own power and it isn't always a continuous effect.
Debuff vs. Set Atk
Set Atk (exclusive to Tengu) is a skill that allows to decrease Atk point of an enemy unit as well.
Differently from Debuff, it works on units that spawn from that moment onwards (while Debuff tends to work on already placed units), it lowers to a fixed value (while Debuff lowers by a fixed value) and it's only temporary (while Debuff tends to be permanent).
Note about Debuff
While it's only a cosmetic bug which doesn't actually affect the game, it's worth noting that the Debuff icon in the filter doesn't match what it's supposed to do, with a more fitting one including a sword rather than a heart: