Detect Thoughts

[Olaf the Stout]

If I cast Detect Thoughts on someone and they fail their saving throw do they know that someone is detecting their thoughts?

Would using Detect Thoughts on someone make an invisible caster visible again?

What is regarded as "surface thoughts"?

Do you think that you could use it to see if a room was empty or if there was an invisible or hidden creature in the room?

[sblock=Detect Thoughts]

Detect Thoughts

Divination [Mind-Affecting]
Level: Brd 2, Knowledge 2, Sor/Wiz 2
Components: V, S, F/DF
Casting Time: 1 standard action
Range: 60 ft.
Area: Cone-shaped emanation
Duration: Concentration, up to 1 min./level (D)
Saving Throw: Will negates; see text
Spell Resistance: No

You detect surface thoughts. The amount of information revealed depends on how long you study a particular area or subject.

1st Round
Presence or absence of thoughts (from conscious creatures with Intelligence scores of 1 or higher).

2nd Round
Number of thinking minds and the Intelligence score of each. If the highest Intelligence is 26 or higher (and at least 10 points higher than your own Intelligence score), you are stunned for 1 round and the spell ends. This spell does not let you determine the location of the thinking minds if you can’t see the creatures whose thoughts you are detecting.

3rd Round
Surface thoughts of any mind in the area. A target’s Will save prevents you from reading its thoughts, and you must cast detect thoughts again to have another chance. Creatures of animal intelligence (Int 1 or 2) have simple, instinctual thoughts that you can pick up.

Each round, you can turn to detect thoughts in a new area. The spell can penetrate barriers, but 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt blocks it.

Arcane Focus
A copper piece.[/sblock]

Olaf the Stout

 

[Piratecat]

No.

No (I think?).

"Interesting thread. I think I'll... is that my dog barking again? Arrgh! Shut up, dog! Now, where's my glass of milk?" If you want to know if that's my dog, you're all set -- but if you're looking for deep-seated history about my grandparents or even what I did at work today, you're out of luck unless you can get me to think about it.

And yes, absolutely, so long as they weren't blocked by various materials.

 

[Hypersmurf]

If I cast Detect Thoughts on someone and they fail their saving throw do they know that someone is detecting their thoughts?

No.

"A creature that successfully saves against a spell that has no obvious physical effects feels a hostile force or a tingle, but cannot deduce the exact nature of the attack." There's no such wording for a creature who fails.

Would using Detect Thoughts on someone make an invisible caster visible again?

If the area of the spell includes a foe (as perceived by the caster), invisibility considers it an attack. In addition, a spell that an opponent resists with a saving throw is considered an attack by spells in general.

So if you're Detecting Thoughts on your friend, no problem. If you're Detecting Thoughts on an opponent or a foe, invisibility ends.

Do you think that you could use it to see if a room was empty or if there was an invisible or hidden creature in the room?

As long as it's a conscious creature with an Intelligence score of 1 or higher, yes.
The spell won't reveal mindless creatures or unconscious creatures.

-Hyp.

 

[Hypersmurf]

"Interesting thread. I think I'll... is that my dog barking again? Arrgh! Shut up, dog! Now, where's my glass of milk?" If you want to know if that's my dog, you're all set -- but if you're looking for deep-seated history about my grandparents or even what I did at work today, you're out of luck unless you can get me to think about it.

This, of course, is where having your lovely assistant say "Now, whatever you do, don't think about what you did at work today!" works marvels.

-Hyp.