Rules mongrels
Heh - I thought as much. Y'all seem to be reading quite a bit into some simplistic type things...
For example, the relevant section of Alter Self:
From the SRD said:
You assume the form of a creature of the same type as your normal form. The new form must be within one size category of your normal size. The maximum HD of an assumed form is equal to your caster level, to a maximum of 5 HD at 5th level. You can change into a member of your own kind or even into yourself.
You retain your own ability scores. Your class and level, hit points, alignment, base attack bonus, and base save bonuses all remain the same. You retain all supernatural and spell-like special attacks and qualities of your normal form, except for those requiring a body part that the new form does not have (such as a mouth for a breath weapon or eyes for a gaze attack).
You keep all extraordinary special attacks and qualities derived from class levels, but you lose any from your normal form that are not derived from class levels.
and the relevant section of Polymorph:
From the SRD said:
This spell functions like alter self, except that you change the willing subject into another form of living creature. The new form may be of the same type as the subject or any of the following types: aberration, animal, dragon, fey, giant, humanoid, magical beast, monstrous humanoid, ooze, plant, or vermin. The assumed form can’t have more Hit Dice than your caster level (or the subject’s HD, whichever is lower), to a maximum of 15 HD at 15th level. You can’t cause a subject to assume a form smaller than Fine, nor can you cause a subject to assume an incorporeal or gaseous form. The subject’s creature type and subtype (if any) change to match the new form.
Upon changing, the subject regains lost hit points as if it had rested for a night (though this healing does not restore temporary ability damage and provide other benefits of resting; and changing back does not heal the subject further). If slain, the subject reverts to its original form, though it remains dead.
The subject gains the Strength, Dexterity, and Constitution scores of the new form but retains its own Intelligence, Wisdom, and Charisma scores. It also gains all extraordinary special attacks possessed by the form but does not gain the extraordinary special qualities possessed by the new form or any supernatural or spell-like abilities.
Incorporeal or gaseous creatures are immune to being polymorphed, and a creature with the shapechanger subtype can revert to its natural form as a standard action.
Now for some points
1) Notice that "alter self" does not change types of the caster
2) Notice that "alter self" says "Your class and level, hit points, alignment, base attack bonus, and base save bonuses all remain the same."
Base attack bonus, Base save bonus... wonder why they said BASE? Even though it states clearly that CON and STR can't change...
3) Notice that both Alter Self AND Polymorph increase HIT DIE. One up to 5 HD, the other up to a max of 15.
4) Notice that Polymorph clearly indicates that CON changes.
5) Also notice that you are actually changing FORMS (i.e. types) under polymorph.
Now, if you recall, we wondered why Alter Self had stated 'base' in front of attack bonus and save bonus? Because, quite simply, polymorph allows the modifiers to these to change with the changing str, con, and dex. If the modifiers to these can change, then yes, the modifiers to 'hit points' should also change.
I.E. Your hit points remain the same. Your CON modifier to your hit points changes. This can be both good and bad, if you think about it.
I have not seen any other rule, ruling, clarification, errata, or just plain statement that would indicate that a gain in HD does not result in a gain in your attack modifiers, your save modifiers, and yes, your hit point modifiers.
That doesn't mean it doesn't exist, necessarily. I just haven't seen it and would love to see some reference to another instance like the one trying to be cited here. In other words, can you find any other situation in which your CON changes and your hit points don't???
All of that said, you can argue interpretations all week in saying that polymorph states "like alter self, except" for both sides of the arguement. Or you can just take polymorph as a whole and apply the fact that no where else does a con increase NOT increase hit points!
Personally, I think it nerfs quite a bit of polymorph to not let it change the hitpoints. Also, it becomes a little silly if you have polymorphed a dragon into a rabbit that has 300 hitpoints... and a CON of 5.
I suspect that neither side will stop arguing - simply because it can be argued, and therefore 'should' be... The rule's aren't perfect, and intrepretations occur. Where intrepretations occur, you find the roots of lawyers.
