[Shostak]

Originally Posted by phiwum

Suppose an item has five Conceal spells on it (which is, oddly, typical).

Even with two Conceals, Spellsniffer will detect about 50% of the time for someone with IQ 17. Although the first two Conceals have a negligible casting cost, a third is pretty exhausting, and the fourth and fifth cost 16 and 32 ST, respectively, putting them out of reach for most wizards working alone. By contrast, Spellsniffer is far more economical. It is reasonable to believe that anything detected but unanalyzed will be subjected to Reveal spells by a seriously inquisitive wizard.

There are a few ways to read the Spellsniffer spell as a continuing spell. One question is: suppose I've rolled for Detect and (if necessary) Analyze magic for each spell/magic item in my range on turn one. Do I get to try again on turn 2 for those that I've failed? Or do I just get to try "new" spells and items entering my range? (The former is more plausible, but if you wanted to nerf it, here's one place to do so.)

I think the spell description implies the former, which is a major factor in why I think Spellsniffer is far overpowered.

And, suppose on turn 1 I detected magic on the cheese grater, but I didn't analyze it. On turn 2, do I have to re-detect in order to analyze or do I just go to analyze? Again, it seems plausible that you go straight to analyze on turn 2, but if you want to nerf the spell, then you can think of it as "memory-less" -- each turn it has to detect prior to analyzing.

The description is unclear on this point, but it doesn't specifically mention losing detection each turn. If one discontinued the spell without successfully analyzing something detected, it would make sense to have to make the detect roll again if Spellsniffer is recast, but as long as it is maintained, it seems to me that anything detected remains detected.