Immunity: Just how much protection does it provide?

[NMcCoy]

I grok resistances, but Immunity seems a little weird. If something has "Immune X", does that mean that powers with the X keyword don't affect it at all? Suppose I'm a Wizard, and blast a Rotwing Zombie (Immune: disease, poison) with Lightning Serpent (Arcane, Implement, Lightning, Poison; Hit: 2d12 + Intelligence modifier lightning damage, and the target takes ongoing 5 poison damage and is slowed (save ends both).)

The MM wording for Immune is as follows:

Immune: The monster has immunity to the stated kind of damage or effect. For example, a monster with “immune poison” never takes poison damage and can’t suffer any other ill effect from a poison attack.​

There are two ways I can see this going, basically - either it's immune to everything that has the Poison keyword, meaning it's not affected by the attack at all, or the lightning damage doesn't count as "any other ill effect" and so it takes the lightning damage but isn't slowed. The latter would seem to be the more sensible interpretation, but I'm not sure what the proper ruling is.

It would seem, after all, that you can use a Staff of Fiery Might to reroll the damage on Blazing Starfall even if you aren't a Cosmic Magic Sorcerer. But can you safely drop a Blazing Starfall on your Fire Lizard familiar?

 

[Tremorsense]

I was about to side with the MM rule, but in the PHB (page 55, Keywords) it says:

Resistance or immunity to one keyword of a power does not protect a target from the power’s other effects.

I don't think you'll find an official rule either way. Although in the case of familiars it would seem best to use the MM rule so the fire lizard can be safe, I would play it the other way so that things like Lightning Serpent don't end up useless in some situations.

 

[DracoSuave]

Immunity to X does make you completely immune to all powers with the keyword X. This is because such powers have that keyword for -all their effects.- The rule 'Resistance or immunity to one keyword of a power does not protect a target from the power’s other effects.' does have two applications, however:

1) If I were to use a power that grants me bonus fire damage, if you have immunity to fire, then you are immune to the fire damage. However the rest of the power does not have the fire keyword, and therefore you are not immune to it.

2) Some powers have effects that themselves have a keyword that the rest of the power does not. Warden's 'Form of the _____' dailies, for example, do not have the keyword Weapon, however, they have attacks that -explicitly- gain the keyword. If, for instance, you had someone who had immunity to weapons, they could use the Form power to polymorph themselves. If the power had the Weapon keyword, tho, someone with immunity to weapons would -not- be able to polymorph themselves.

Another example is in Martial Power, there is an attack that does not have the fear keyword, but has an effect that states 'This has the fear keyword.' Immunity to fear gives immunity to that effect but not the entire power.

There are also attacks in the PHB2 that have one attack type, but then give another attack with another attack type. Swarms, for example, would be resistant to a Ranged power, but vulnerable to it's secondary attack if that secondary attack were a 'area burst.'

 

[Starfox]

With resistance, you have to be resistant to all keywords of a multi-keyword attack if you want to apply your resistance. It makes sense that the same applies to immunity. So, in this case, you'd be immune to any damage that was specifically poison damage, but not to the whole power unless you were also immune to the other keywords.

 

[CapnZapp]

With resistance, you have to be resistant to all keywords of a multi-keyword attack if you want to apply your resistance. It makes sense that the same applies to immunity. So, in this case, you'd be immune to any damage that was specifically poison damage, but not to the whole power unless you were also immune to the other keywords.

But this would be a houserule, no?

 

[DracoSuave]

With resistance, you have to be resistant to all keywords of a multi-keyword attack if you want to apply your resistance. It makes sense that the same applies to immunity. So, in this case, you'd be immune to any damage that was specifically poison damage, but not to the whole power unless you were also immune to the other keywords.

Immunity to poison gives you immunity to all parts of the power that have the poison keyword.

Poisoning Attack!!! Dudefella Attack 9
Daily - Arcane, Poison, Implement
Standard Action - Ranged 10
Target: One creature in range
Attack: Constitution vs AC
Hit: The target is immobilized and takes ongoing damage 10 (save ends both)
Effect: The target takes 1d10 + Constitution poison damage

Looking at this power, we see the Poison keyword in the Keyword line. That means that this power's effects are poison effects. The hit line? A poison effect. The effect line? Poison effect. Also, all of those are also Arcane effects and Implement effects.

Now, first, resistance and immunity are -completely different things.- Damage types and keywords are -different things.-

Resistance -only affects damage- and -damage types-. So Resistance to poison 10 would only apply to the poison damage, and not to the ongoing damage.

Immunity to Poison, however, applies to keywords -and- damage types. So it means you don't take poison damage, but it also means you don't take poison effects.

 

[77IM]

For me, the key is making sense of this line from PHB p.55:

Resistance or immunity to one keyword of a power does not protect a target from the power’s other effects.

This line seems to contradict what Draco is saying and conflicts somewhat with the MM entry for Immune. Let's take out the part about Resistance because the "or" means it should still be logically valid:

Immunity to one keyword of a power does not protect a target from the power’s other effects.

This seems to say that if you are immune to poison, and get hit with lightning serpent, you are not immune to the lightning damage, but are immune to the poison damage. If poison immunity made you immune to every part of the power, the above quote would be invalid.

The question of whether the slow effect is a poison effect or not is more interesting. I'm going to go with a modification Draco's interpretation for this -- non-damaging effects get all the keywords of the power; but damaging effects helpfully tell you which keywords they use. So the hit from poisoning attack!!! could still damage a poison-immune creature since it is untyped damage, but the creature would not be immobilized.

Starfox's interpretation is interesting but I think it leads to an absurd situation: Almost every PC power is going to have a power-source keyword and usage keyword, and very few monsters are running around with "Immune arcane" or "Immune encounter." This could force us to distinguish our keywords, but that's tricky because of keywords like Charm and Fear and Reliable and Rattling, which are neither damage keywords nor source/usage keywords.

-- 77IM, thinks "immune encounter" could make a really interesting monster

 

[CapnZapp]

Problem is when your houserule means each power needs to be interpreted individually.

I think immunity was intended to be a whole class better than resistance, and something much more special.

If you're immune to Cold, instead of merely resistant, you are made of fundamentally different stuff. This makes you immune to all Cold powers, even if they also deal separate Lightning damage.

In this I don't think the PHB is ambigous (once you focus on the Immunity rule and not that page 59 quote). Any uncertainty instead comes from how people feel the rule "should" work.

 

[77IM]

In this I don't think the PHB is ambigous (once you focus on the Immunity rule and not that page 59 quote). Any uncertainty instead comes from how people feel the rule "should" work.

I dunno, I feel like I examined this question with an open mind, based on what was in the text (all the relevant passages).

I think immunity was intended to be a whole class better than resistance, and something much more special.

If you're immune to Cold, instead of merely resistant, you are made of fundamentally different stuff.

To me, this sounds like a statement of how the power "should" work, rather than an argument based upon the text.

I'm not saying your interpretation is wrong (is it even possible for an interpretation to be wrong in this context?), just that it doesn't seem to be any more supported than the other interpretations, considering that the MM and PHB passages are contradictory and don't define "effects" and "other effects" very well.

-- 77IM

 

[NMcCoy]

Just adding more fuel to the fire here: What exactly happens if I hit a bloodied Rage Drake (immune to fear while bloodied) with Dire Radiance?

At-Will * Arcane, Fear, Implement, Radiant
Standard Action Ranged 10
Target: One creature
Attack: Constitution vs. Fortitude
Hit: 1d6 + Constitution modifier radiant damage. If the target moves nearer to you on its next turn, it takes an extra 1d6 + Constitution modifier damage.​