Nail said:
If I put a knife in your gullet, would that be a "vital spot"?
The argument about the interior of the gullet not being a vital spot is ....reaching, IMO. The gullet does not have separate hp. It's part of the creature -- and right next to the heart, lungs, etc...
In fact it is NOT self-evident that the gullet is not a vital spot in and of itself.
Sure, it's reaching. Gullet's which close with muscular action are, however, patently ridiculous. Swallowing monsters just require a little suspension of common sense. Frankly, the fact that you can attack at all after being chomped by a huge mouth and then immersed in powerful acid, while you're constantly churned about by the digestive tract is already far-fetched.
Given that "grappling, cramped" setting, I don't think it's reasonable to allow much in the way of fine control - the type of fine control a sneak attack would require. Allowing for the existence of swallowing monsters, it's simply inconsistent to image they would use a strategy which makes themselves so much more vulnerable - but that's how this would work out.
A D&D swallow-whole enabled monster gullet clearly isn't just any gullet - that just doesn't make sense on many levels. I doubt whether a rogue could percieve much of anything - even with darkvision - inside a gullet. Frankly, any normal humanoid would be instantly blinded by the acid, so presumably, a rogue has his eyes closed (and rather acid-repellent eye-lids too), and is holding his breath, and can't do much but poke about. Even if you're immune to the acid damage, digestive juices aren't transparent, and a blind creature can't make sneak attacks. Apparently it's possible to cut yourself out without hitting a vital area, so it's certainly not a give that any strike hits a vital area. You can't perceive the vitals, and not everything is vital; thus you have no sneak attack. Even if you could perceive the gullet (not that I can see how), no reasonable PC can be experienced in finding the vitals in a gullet which visually probable resembles an ooze more than an animal, so mere rogue-sneak attack would not suffice.
Finally, game mechanics wise, you're grappling the gullet. It's in constant contact with you, and there's no mechanical reason it would be flatfooted (or have otherwise lost it's non-existant Dex bonus), and thus you cannot sneak attack.
A rogue already has a big advantage in any swallowing situation in that he'll actually have a light weapon in hand, generally. The fighter, cleric and mage won't be so lucky, usually, and a monk deals bludgeoning damage. Barring that, escape artist is a rogue-skill, and almost only rogues will have it.
Ultimately, there is a short bit of rules which describes swallow whole. Deviating from these rules by allowing many more activities is asking for trouble. Sneak attack isn't explicitly allowed by swallow whole, and there's no balanced framework I can see for doing so, and I would not allow it.
We have
- Cognitive dissonance: Why would a swallowing creature expose itself so systematically to harm it can have no protection against?
- Cramped quarters would make precise movements tricky
- Visibility: you can't see inside the gullet, because the juices are not transparent.
- No mechanical reason to assume the gullet is flat-footed.
- Balance: allowing sneak attack would mean the rogue often wants to be swallowed, since it means he can consistently use his most powerful attack, while generally being protected from almost all attacks of the swallower (except the acid and bludgeoning damage).