Detect Evil versus Evil Celestial?

[Elzak]

Quick Question:

What will happen if a paladin cast his detect evil on a celestial who has evil alignment, for example, Trias from 'Planescape: Torment'?

Will the spell be fooled even when the celestial mentioned above eating babies, kicking puppies, tying hapless maiden on a railroad track right under the paladin's nose?

[Inevitability]

An evil celestial would detect both as a Good outsider (because of its subtype) and an Evil outsider (because of its actual alignment), so Detect Evil picks it up just fine.

[Malimar]

A creature interacts with effects as its actual alignment and the alignment of its subtypes.

Detect Evil would detect the celestial's Evil alignment. Detect Good would detect the celestial's Good subtype.

[Elzak]

Well, darn, there goes my plan A for countering those pesky detect alignment.

Guess I'll just grab some good-old nondetection or mindblank, thanks for reply!

[Crake]

Well, darn, there goes my plan A for countering those pesky detect alignment.

Guess I'll just grab some good-old nondetection or mindblank, thanks for reply!

Nondetection is unreliable, have you considered the spell "undetectable alignment"? It's a 1st level bard spell, 1st level beguilder spell, 2nd level cleric spell, hell it's even on the paladin, assassin, and blackguard list iirc. If you get a beguiler to make an item of continuous undetectable alignment it would cost a measly 1000gp, so really, hiding your alignment is not even close to an issue.

[Kish]

Although that has another downside to it, should anyone think of using Detect Good near the celestial. ("Why do you appear to have no alignment at all? You must be an illusion of a celestial!")

[KillianHawkeye]

Fun fact: Eludecia, the Succubus Paladin from one of WotC's web articles, counted as all four alignments for the purposes of spells and effects. She was a Lawful Good demon with the Evil and Chaotic subtypes.

[Andezzar]

If you get a beguiler to make an item of continuous undetectable alignment it would cost a measly 1000gp, so really, hiding your alignment is not even close to an issue.That is if the DM decides that this item is worth only 1000 gp. The first step to finding a price for a custom magic item should be to compare it to standard magic items in terms of usefulness. The formula is only a guideline.

If you are an arcane spellcaster, an eternal wand of undetectable alignment should also work. This already has a fixed price (820 gp).

[Yogibear41]

Although that has another downside to it, should anyone think of using Detect Good near the celestial. ("Why do you appear to have no alignment at all? You must be an illusion of a celestial!")

I believe there is a spell similar to undetectable alignment that instead makes you appear as a particular alignment, although I cannot remember its name at the moment.

[RedMage125]

Fun fact: Eludecia, the Succubus Paladin from one of WotC's web articles, counted as all four alignments for the purposes of spells and effects. She was a Lawful Good demon with the Evil and Chaotic subtypes.

Even more fun facts about her...
She'd take damage from Holy Smite, Unholy Blight, Chaos Hammer and Order's Wrath.

When she's killed, the energies that make up her body will return to the Abyss and make a new (likely CE) succubus.

There are rituals in Savage Species that she could pay to go through that would remove the Chaotic, Evil and Tanar'ri subtypes from her (well, the alignment ones would be traded for Lawful and Good). If they were removed, she'd no longer suffer from effects as a chaotic or evil creature. And presumably when she died the energies making up her body would go to a celestial plane and form a 6-HD (her racial HD) celestial of some kind, probably a hound archon.