Mask of a Thousand Tomes + Invisibility

[Warped Savant]

If someone were to make a Mask of a Thousand Tomes invisible would the wearer be able to see normally and still gain the +10 to Knowledge checks?
The blinded condition appears to be from the mask not having eyes in it rather than a supernatural effect.

Thoughts?

[Yomabo]

If a player of mine would ask this, I would say no.
Would you get an armor bonus if you would hide behind a set of +5 full plate armor, but not the armor penalty?

[Quixote]

Warped Savant wrote:

The blinded condition appears to be from the mask not having eyes in it rather than a supernatural effect.

It may have intended to be, but that's not how it's written. It's a magic item. It's effects include blinding the wearer and granting a +10 to Knowledge checks.

[Azothath]

The item description contains the blindness effect so it is a function of the item.

analysis
from the Table: Estimating Magic Item Gold Piece Values the listed price for a skill competence bonus is 100*B^2 {B is the bonus}.
> You don't need continuous as the reference is always on/continuous in a body slot.

> Item Requires Skill to Use: Some items require a specific skill to get them to function. This factor should reduce the cost about 10%.
Knowledge skills are Trained only. Without 1 rank the competence bonus is of no value. As this is 10% and I use the less costly method below, ignoring this is reasonable.

> Eyes slot: generally perception and some skills.
This is the correct slot.

+10 comp in eyes slot (to a perception type check) should cost 100*(10^2)=10000GP for ONE skill. However the mask affects ALL skills.
A popular method is to add 1.5*cost for every extra ability.
Another method is to use multiple similar abilities. That is less expensive and adds by extra abilities; 2nd*0.75cost, 3rd and more*0.25cost.
There are 10 basic knowledge skills, so 1 +0.75 +8*0.5=5.75 cost multiple. So the item without the blindness should cost 57500GP at a minimum using the multiple similar abilities method.
This lets you know the blindness offers a significant discount on the item.
For game balance and costing a simple spell isn't going to negate the effect.

[Warped Savant]

These thoughts all align with my thinking too, but I was curious to see what others thought, just in case.
(The cost is a major part in why I was thinking it wouldn't work. Thank you for the thorough answer and math, Azothath.)

[Azothath]

Warped Savant wrote:

These thoughts all align with my thinking too, but I was curious to see what others thought, just in case.

(The cost is a major part in why I was thinking it wouldn't work. Thank you for the thorough answer and math, Azothath.)

The alternative is a Lore Needle spamming the ranks in one skill 3* per day. There can be slot conflicts and this item has a nasty effect with failure on 'donning'.

[blahpers]

Most arguments that would conclude blindness works/doesn't work while the mask is invisible could reasonably apply to the Knowledge boost working/not working. Either you get both or you get neither. If my player were crafting this item, I'd let them decide which.

[Bob Bob Bob]

The rules are pretty clear, the mask blinds you. Not "the mask blocks vision" it just straight up blinds you. Personally I always figured it was like those face computers they love in sci-fi. You put it on and when you think of something it pulls up the relevant part of the appropriate book and displays it. Making it invisible would make it completely useless. That way also implies you could make a miniaturized version if you can take the DBZ jokes.