Living Mask vs. Mindsight...

[ksbsnowowl]

This item, from Ghostwalk, was brought up in the Fun Finds thread.

Living Mask: This one-use magic item functions as soon as a wearer puts it on, and stops as soon as it is taken off, becoming powerless. It works only when worn by an undead creature. Each mask provides an illusion that the wearer is alive, albeit a living person wearing a theater mask and clad in fine clothing. The undead appear alive not only to the senses, but also to spells such as detect undead and deathwatch. These items allow people with undead minions to walk about the city if need be.
If these items were known to exist, the government of Manifest would declare them illegal.
Caster Level: 3rd; Prerequisites: Craft Wondrous Item, change self or disguise undead, misdirection; Market Price: 400 gp; Weight: 1 lb.

Mindsight
A creature that has this feat possesses innate telepathic ability that allows it to precisely pinpoint other thinking beings within range of its telepathy. The creature perceives where the others are and how powerful their intellects are.
Prerequisite: Telepathy special quality.
Benefit: A creature that has this feat can detect and pinpoint beings that are not mindless (anything with an Intelligence score of 1 or higher) within range of its telepathy. This works much like blindsense—the creature knows what square each thinking being is in, but it does not see the being, and the being still has total concealment unless the creature can see it by some other means.

The creature also perceives several observable characteristics about each being detected with mindsight, including the being’s type and Intelligence score. The creature need not take any additional or special actions to gain this information; it is as obvious to mindsight as the being’s race and clothing would be to eyesight.
Normal: Telepathy offers no special ability to sense other minds. The creature has to know that a being is there to communicate with it telepathically.

So, does the masked undead still detect as undead to mindsight?

[NunoM]

I'd rule that the mask camouflages the creature's type.

Mindsight mentions the creature identifies observable characteristics, and the mask, by looking at the spells used in it's manufacture, was clearly designed to avoid simple observation.

[zook1shoe]

Mindsight is a mental sense, which would be blocked by the mask

[linklord231]

Mindsight is a mental sense, which would be blocked by the mask

Agreed.  Which begs the question, what type does Mindsense perceive the masked creature as?  It's kind of a dead () giveaway if you can't sense their type, when you normally can. 

[ksbsnowowl]

It says they have an illusion of being a living person, so I would assume they detect as Humanoid.

[linklord231]

It says they have an illusion of being a living person, so I would assume they detect as Humanoid.

Even if they used to be an aberration or dragon or something before they became undead?  Or what about creatures that never had a type before they were undead, like Nightcrawlers?

[ksbsnowowl]

I'm just going off what the item itself says:

Each mask provides an illusion that the wearer is alive, albeit a living person

As we know from Charm Person, etc, "person" means humanoid in probably every instance of the core rules.

[zook1shoe]

A person is a creature w a mind, there is no rule stating that. But it makes sense.