Fire Truth (Divination) (Province: Flame)
Level: 1
Range: 5 yds. 
Components: V, S, M 
Casting Time: 1 turn 
Duration: 10 rds.
Area of Effect: 1 creature 
Saving Throw: None
By means of this spell, the caster and those accompanying him can determine whether someone speaks the truth or knowingly lies. A special candle serves as the material component of this spell (see below). Its flame is fed by the veracity of the target individual's words—whether they're spoken aloud or given in sign language.
When casting the spell, the wizard lights the candle in the presence of the target (no farther than 5 yards away). The wizard himself must question the target. The candle remains lit as long the target answers truthfully. An intentional halftruth or slight deception causes the flame to gutter. An outright lie extinguishes the flame, ending the spell.
Otherwise the spell lasts 10 rounds, or for 10 questions, whichever comes first. At the end of that period, the flame flares brightly, then goes out. Truth is subjective to the target. If the target truly believes something, then the candle registers it as truth. “I don’t know” or a similar response has no effect on the candle if the target is truly ignorant.
The fire truth spell allows no saving throw, but it can be rendered useless by other magics, such as a philter of glibness or the spell undetectable lie (reverse of the priest spell detect lie) or its equivalent.
The fire truth spell is used most often in business and matters of state, where veracity is important, and the target creature is (supposedly) willing and interested in telling the truth. When signing a contract, for example, that target is often asked to verbally attest to his honesty. (“Do you swear that the information here is true? Do you plan to uphold this contract?”)
The candle required for this spell is made of a rare form of desert bee's wax. It costs 300 gp ready-made, and is usually available only through holy men (usually moralists). The wizard can make the candle himself in a week, after investing 100 gp in the raw materials, if available.
Notes: Common in arabian settings; unknown elsewher