If you have a wand of Summon Monster, or a staff that has the spell, you can usually choose what you're summoning when you use that charge. Except when you can't, like the Staff of Spiders or Staff of Hungry Shadows, which both limit what can be summoned with those spells.
Does this reduce the price of the wand/staff at all? Or would you, as a GM, reduce the cost to craft or buy the item?
The hungry shadows staff seems to be priced lower than its spell complement would otherwise require, though Spiders seems to be overpriced. So I'm not able to get a good read on any consistent factor.
Thanks, in advance.
The staff of spiders is priced just about exactly right since it is also a +1/+1 double weapon.
It isn't explicitly stated that it is required in the rules, but the published staffs all have a strong theme so that the spells are related on some way. My guess would be the designers consider limiting these spells so the fit the theme to be a trade off for the versatility that is lost (in other words, if you didn't limit it, you couldn't get it.)
Staffs are a hard one for me to make a personal call on since I think they are pretty much all heavily overpriced. Summon monster is still just about as powerful a spell without the choice so I wouldn't see much of a discount for that, something like resist energy (only being able to choose one) I would be more likely to consider a discount.
Just checked. Both staves are priced exactly by formula. There is no discount given for the limited selection of the spell.
/cevah
I can definitely say, as a GM, I wouldn't let a player have a reduced price for only being able to summon one type of creature, since most of the time creatures will be chosen for what is the strongest option available, which means it's not a real limit on the power of the spell.
If I were designing the item myself, for a thematic staff which could only summon non-optimal choices I might prorate the value a bit.