Any reason why these two couldn't be cast one after the other, in that order? And any reason why their bonuses wouldn't stack for the duration?
I'm asking on behalf of our burgeoning Dragon Disciple - I assume an existing Mage Armor spell (or other buffs) also would be unaffected by the two castings, yes?
Can't see any reason why those bonuses wouldn't stack. You should be fine- and EXTREMELY nasty.
And Mage Armor wouldn't be affected.
Well, the rules for Polymorph subtype spells state that you cannot cast spells with material components when in animal, dragon, elemental, magical beast, plant or vermin shapes.
This is a problem for Transformation, which has a material component (a potion of Bull's Strength). Since all your gear melds into the dragon form, you couldn't access your potion to consume it and cast Transformation.
However, the Polymorph section does say, "...unless you have the Eschew Materials or Natural Spell feat." Since the PC is a sorcerer, he has Eschew Materials as a bonus feat. Even though the feat doesn't apply to the potion, RAW it still lets him cast spells with material components if he can lay his hands on them while polymorphed. So if another party member hands him the requisite potion of bull strength after casting Form of the Dragon, he could then cast Transformation.
Dragons are the specific example cited of a form capable of somatic and verbal components, so the rest of casting the spell if easy enough.
Transformation is not a Polymorph effect, nor does it change your size, so it seems to be fair game to cast (if you can work out the potion component).
As for the effects stacking, everything looks good except the Natural armor bonuses. Both seem to provide a base +4 Natural Armor bonus (neither spell states it increases natural armor or provides an enhancement bonus). Thus, they appear to overlap.
Pre-existing buff spells would remain in effect, subject to the laws of stacking (no size increasing spells due to polymorph, no second polymorph due to polymorph, only the higher of enhancement bonuses, etc). But if he is looking at pre-casting things like Mage Armor and Blur for defense, then yeah they keep running.
Well, the rules for Polymorph subtype spells state that you cannot cast spells with material components when in animal, dragon, elemental, magical beast, plant or vermin shapes.
This is a problem for Transformation, which has a material component (a potion of Bull's Strength). Since all your gear melds into the dragon form, you couldn't access your potion to consume it and cast Transformation.
However, the Polymorph section does say, "...unless you have the Eschew Materials or Natural Spell feat." Since the PC is a sorcerer, he has Eschew Materials as a bonus feat. Even though the feat doesn't apply to the potion, RAW it still lets him cast spells with material components if he can lay his hands on them while polymorphed. So if another party member hands him the requisite potion of bull strength after casting Form of the Dragon, he could then cast Transformation.
Dragons are the specific example cited of a form capable of somatic and verbal components, so the rest of casting the spell if easy enough.
Transformation is not a Polymorph effect, nor does it change your size, so it seems to be fair game to cast (if you can work out the potion component).
As for the effects stacking, everything looks good except the Natural armor bonuses. Both seem to provide a base +4 Natural Armor bonus (neither spell states it increases natural armor or provides an enhancement bonus). Thus, they appear to overlap.
Pre-existing buff spells would remain in effect, subject to the laws of stacking (no size increasing spells due to polymorph, no second polymorph due to polymorph, only the higher of enhancement bonuses, etc). But if he is looking at pre-casting things like Mage Armor and Blur for defense, then yeah they keep running.
I really appreciate the detailed response. We'll probably house rule that with Eschew Materials the spell will function just fine but the potion will indeed be both required and expended regardless. Having someone hand him the potion after he's become a dragon in the middle of combat just seems a little to much like missing the forest for the trees, you know?
In our home games, we've decided that natural armor bonuses (as well as the ever-confusing bonuses TO natural armor) all stack, so that shouldn't be a problem, but I feel its important to understand even the rules that you've changed.
FWIW, we also did away with SR, changing it to a generic +4 bonus to save vs. spells as it was decided that defeating Spell Resistance and THEN beating a Saving Throw and THEN overcoming elemental resistance, etc. was just getting a bit too silly to have one spell work as intended.
Metamagic Rod of Delay Spell?
Just of note, there is also this Polymorphic Pouch that does not merge with forms and allows access to such items, from what I understand of it.
Would the bonus hit points gained from increases in Constitution work like those gained from barbarian's Rage, i.e. damage remains when bonus hit points fade, or would it work more like temporary hit points (lost first) that can be healed while the spell is in effect?
If the hit points gained were temporary, it would say so in the spell.