Undead and negative levels

[TuggyNE]

So, I've been wondering: are undead and constructs immune to all negative levels, or merely those caused by negative energy or from creatures with energy drain attacks? It's not clear, because the entry on energy drain is titled "Energy Drain and Negative Levels (http://www.d20srd.org/srd/specialAbilities.htm#energyDrainAndNegativeLevels)", but doesn't equate them fully, and in other places they don't seem to be identical.

It seems reasonable that, say, a Holy weapon should be able to affect them negatively, and it's handy if there could be a spell that just gives them negative levels without having to tediously invoke a bunch of boilerplate "exactly like negative levels except it works on undead!"

[Pickford]

So, I've been wondering: are undead and constructs immune to all negative levels, or merely those caused by negative energy or from creatures with energy drain attacks? It's not clear, because the entry on energy drain is titled "Energy Drain and Negative Levels (http://www.d20srd.org/srd/specialAbilities.htm#energyDrainAndNegativeLevels)", but doesn't equate them fully, and in other places they don't seem to be identical.

It seems reasonable that, say, a Holy weapon should be able to affect them negatively, and it's handy if there could be a spell that just gives them negative levels without having to tediously invoke a bunch of boilerplate "exactly like negative levels except it works on undead!"

Two distinct concepts. Negative levels can result from energy drain, but in the case of constructs and undead, energy drain is what they are not subject to.

Negative levels would still happen if, for example, a lich put on a good aligned robe of the archmagi.

[The Viscount]

I've never really thought about it, but I suppose undead technically are subject to negative levels if from a non-energy drain source. It seems solid enough to me, as there are legitimately things besides negative energy based effects that give negative levels, just as undead are subject to mental ability damage in the right circumstances.

[Story]

just as undead are subject to mental ability damage in the right circumstances.

Isn't this the default? The Undead type description specifically only provides immunity to physical ability damage. What are the "right circumstances"?

[Frosty]

Being hit a non-mind-affecting effect that targets the mental attributes and also does not offer a fort save.

[The Viscount]

Being hit a non-mind-affecting effect that targets the mental attributes and also does not offer a fort save.

This. Thank you, Frosty. You'd be surprised how many things that would damage a mental ability score are negated by some of undead's other immunities. The only working ones that spring readily to mind are corrupt spells and maiming strike with penatrating strike or truedeath crystal.