Detect Magic interacting with Negative Levels debuff

Question

While alone, one of my teammates had been Energy Drained by a creature. We cast Detect Magic on the teammate and to determine if there were any magical effects. Reading the rules, it doesn't say anything about Negative Levels being magical nor does it belong to any school.

My question is

1. Would Detect Magic be able to detect the magical level?
2. Would there be any way to detect Negative Levels if it was casted by a spell?
3. Would there be any way to detect Negative Levels if it was casted by a Supernatural?

Edited: To elaborate, the player who had the negative levels knew he had the negative level after an event with a succubus while he was alone. The scenario occured because the rest of the party were wondering why he was weaker than usual. The party had no knowledge of the succubus as well.

Answer 1

Only Indirectly and Vaguely

While one or more negative levels are often the result of spells (e.g. energy drain, enervation) and supernatural abilities (e.g. a wight's slam attack's energy drain), negative levels are not, in themselves, magical. The spell detect magic has no direct interaction with the presence or absence of negative levels.

But magic auras from spells recently cast do linger, and those auras can be discerned using the spell detect magic.

A magical aura lingers after its original source dissipates (in the case of a spell) or is destroyed (in the case of a magic item). If detect magic is cast and directed at such a location, the spell indicates an aura strength of dim (even weaker than a faint aura). How long the aura lingers at this dim level depends on its original power...

as per this chart:

Original      Lingering Aura     Spell
Strength         Duration        Level
------------------------------------------
Faint            1d6 rounds    3 or less
Moderate         1d6 minutes   4 to 6
Strong        1d6x10 minutes   7 to 9
Overwhelming     1d6 days      10 or more

Thus, even a few minutes after the spell enervation is cast on some poor dude, there remains a lingering moderate aura of necromancy on him that might indicate to whoever discerned the aura and, subsequently, the school of that aura that the spell caused the negative level.

As Zachiel's answer mentions, though, when the character gains 1 or more negative levels it's usually instantaneous and--probably, in itself,--an undetectable event, the effects of which must be discovered by the character through experimentation. That said, I've never heard of a DM who didn't tell the player his character had gained 1 or more negative levels in an effort to keep such an effect mysterious, but, then again, perhaps the bookkeeping involved has never been worth the narrative reward.

Answer 2

Just like detect magic can tell you nothing about a wound or an ability damage or drain, it can't tell you about negative levels, because negative levels is not a spell or some sort of magical effect, just the result of something (magical or not) removing something from you.

This lack of energy would need a spell specifically searching for it to be detected, but a knowledge or a healing check could probably tell characters about the seriousness of the level loss, and knowing there has been a loss is as automatic as one noticing he has wounds (even if I'm speculating quite a bit because nothing has been written on the matter to my knowledge).

Even if the negative levels were caused by a spell, if the spell has an istantaneous effect it's no more lingering on the subject. It already damaged him and now the character is "ill" and will suffer the consequences unless cured.

Answer 3

Yes. Detect Magic should reveal the presence of a negative level, or any other ongoing magical effect.

The relevant rule section is the (Su) tag on the Energy Drain ability itself. This tags the ability as Supernatural, which means that the effect is "magical but not spell-like," and that places it firmly in the category of a "magical aura" which Detect Magic can detect.

As to the aura strength discovered, the rules are silent as to the general Energy Drain effect and how strong it would appear. Your GM could rule that each negative levels is an individual Faint aura, or he may combine them with each aura counting as a single caster-level.

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To be explicit as to your latter two questions, any spell, spell-like ability, or supernatural ability should leave an aura that can be discovered by Detect Magic. The only ambiguity in the rules with regards to negative levels are if they are a magical effect in and of themselves, or if they are a mundane condition caused by a magical effect.

If your GM rules that Detect Magic does not work, I would expect that either Detect Evil or Detect Undead would. I would personally allow all three in a game I ran, but I would also not complain if a GM ruled that none apply. The rules are not explicit in this manner.