Hi guys! There is some confusion surrounding the topic of Immunity to Debuffs + Immunity to interruption, so I will try my best to help answer this.

First of all, Immunity to All Debuff (such as the passive Itachi Uchiha [Susano'o ] has) is a passive that allows a ninja to be protected from status Debuffs like: Chaos, Immobile, Sleeping, Blindness, Acupuncture, Paralysis, Slow, Poison, Ignite, Tag, and Imprison.

Secondly, Immunity to interruption like the mystery from Killer Bee [Seven Swords Style] will give immunity to interruption to a select unit, which protects a unit from anything that would otherwise normally interrupt or cancel the said unit's mystery.

Thirdly, as said above, there are many different Debuffs and some as you guys know are "Action Impairing Debuffs". What this means is that the debuff can "interrupt" the action of a player while also debuffing the player.

If a unit is "Immune to All Debuffs" and is casting a mystery, but an opponent is either using an Interrupt skill or using an "Action Impairing Debuff", the mystery will be cancelled.

If a unit is "Immune to Interruption" and is casting a mystery (They are immune to interrupt skills), but an opponent is using an "Action Impairing Debuff", the mystery will also be cancelled.

Now here is where the confusion comes in. What happens if a Ninja is both "Immune to All Debuffs" and also "Immune to Interruption".

For example, if a ninja like Itachi Uchiha [Susano'o] (who is Immune to All Debuffs) were to also get "Immune to interruption" from Killer Bee [Seven Swords Style], he would be immune to both interruption and also "Action Impairing Debuffs", which means that a ninja like Masked Man or Shisui would not be able to interrupt Itachi Uchiha [Susano'o] from casting his mystery (This has been tested).

The question is, why is this the case.

The reason for this is because although "Action Impairing Debuffs" do have a secondary effect of interruption and can normally interrupt Itachi Uchiha [Susano'o] from casting Mystery; this secondary effect of interruption is cancelled when Itachi Uchiha [Susano'o] acquired the "Immune to Interruption" from Killer Bee [Seven Swords Style].

This means that not only is Itachi Uchiha [Susano'o] immune to debuffs that can normally stop other ninjas from performing an action, but he is also protected from the secondary effect, interruption, of "Action Impairing Debuffs".

Hope that helps!

~Jib