spellcraft to determine creatures' hitdie

[npiccini]

Recent adventure my party's wizard was facing creatures he had never fought and wanted to know if he could cast Deeper Slumber. Since the spell only affects 10 HD creatures or less, he wanted to know if his character would have any indication of whether the spell would succeed or not. I considered for awhile honestly, since a great number of people have emphasized how hit die aren't real and there is no true world parallel. However, considering certain spells such as Deeper Slumber are effective against only certain HD values, I figured there had to be a way for a caster to guage the potency of a spell in those circumstances.

Naturally the first place I turned to were the, IMO, great articles on WoTC on knowledge of certain creatures. The benchmark there was 10+HD of a creature to determine information a character would know about. The only problem was none of the references in there indicated a creature's hit die. I settled on a spellcraft check with the same rules 10+HD of creature to see if a character could determine a spell's potential effect on a target.

Any input on this ruling? what might others have done?

 

[the Jester]

I probably would have gone with an appropriate Knowledge check based on the creature type. 10 + (base HD) would give the creature's base HD... but the DC would be higher, if possible at all, to determine the HD of an advanced creature or levelled creature.

So the character might learn, "This creatue is a harpy, which is typically within deep slumber's range." They wouldn't have any way of knowing that it's a harpy with 15 rogue levels unless it had some sort of obvious visible effect- expensive looking gear, etc.

 

[Mahali]

I'd also go with an appropriate Knowledge check of 10+HD. Or inappropriate Knowledge skill, Wilderness, or Survival of 15-25+HD.

I wouldn't allow a Spellcraft check at all.

 

[brehobit]

This is why HD (or ECL or CR) should NOT be a part of any spell. Just give the save or not...

But to adress the question, I don't think there is a good answer here. If it is an unknown monster which the PC would have no chance of knowing anything about (unique or whatever) I'd just say no chance. Otherwise I'd say the appropriate knowledge skill. If the baddy if fairly common in the world (the PC would have heard of it before) it might be a reasonable spell-craft thing. (Here is a list of baddies who are generally immune)

Mark

 

[sfedi]

I wouldn´t allow a spellcraft check at all, that´s a Knowledge check.

 

[Ceska]

Knowledge Check.

But the best way to find out: cast the spell and see what happens...

 

[starwed]

There's a feat that lets you get a rough estimate of a creatures/NPCs power with a sense motive check.

That seems appropriate here, as well; sense motive should generally be used to gauge a creature in a non-knowledge based way.

As w/ others, I wouldn't allow spellcraft.