was your eidolon summoned when you got hit with the polymorph?
Personally, I would rule that whichever body it was that was hit is now a turtle until someone dispels it, with all of the abilities of a turtle.
If you were in your regular ol' summoner form, you can't summon your eidolon, because that involves a one minute ritual (Su) which we can safely assume a turtle is incapable of. Baleful Polymorph is quite clear on that point- "It retains any class features (other than spellcasting) that aren't extraordinary, supernatural, or spell-like abilities."
If you are in eidolon form at the time, your situation is a little better, because anything that dismisses/banishes the eidolon should still work on it, restoring you to normal, with, basically, the worst alt-form ever. You would also revert when you go to sleep. I'd personally rule that using a standard action to dismiss it would qualify as using a supernatural ability, so you can't just drop it immediately on getting hit with the polymorph, but that's just me.
Wouldn't this statement... "Neither the synthesist nor his eidolon can be targeted separately, as they are fused into one creature." mean both are effected by the baleful polymorph and when your eidolon returns... you are now just a blue/green turtle with a glowing sigil on its shell?
That would be my read. Unless there is a reason that the polymorph is negated, the eidolon is also stuck in turtle form.
Hello guys, I need your help.
My Synthesist summoner got hit by an effect of baleful polymorph, failed, and became a turtle while keeping my intelligence.
How does it work if I want (if I CAN) to call my eidolon "armor"? Does it work?
Unfortunately the faq aren't that munch precise
Sorry for the bad english
This is sort of in the realm of "up to the GM," but this would be my interpretation.
The Synthesist Summoner includes the following line in regards to how the eidolon and summoner interact when targeted:
While fused, the synthesist loses the benefits of his armor. He counts as both his original type and as an outsider for any effect related to type, whichever is worse for the synthesist. Spells such as banishment or dismissal work normally on the eidolon, but the synthesist is unaffected. Neither the synthesist nor his eidolon can be targeted separately, as they are fused into one creature. The synthesist and eidolon cannot take separate actions. While fused with his eidolon, the synthesist can use all of his own abilities and gear, except for his armor. In all other cases, this ability functions as the summoner’s normal eidolon ability (for example, the synthesist cannot use his summon monster ability while the eidolon is present).
Now, looking at the transmutation (polymorph) subschool, we get the following line:
When you cast a polymorph spell that changes you into a creature of the animal, dragon, elemental, magical beast, plant, or vermin type, all of your gear melds into your body. Items that provide constant bonuses and do not need to be activated continue to function while melded in this way (with the exception of armor and shield bonuses, which cease to function). Items that require activation cannot be used while you maintain that form. While in such a form, you cannot cast any spells that require material components (unless you have the Eschew Materials or Natural Spell feat), and can only cast spells with somatic or verbal components if the form you choose has the capability to make such movements or speak, such as a dragon. Other polymorph spells might be subject to this restriction as well, if they change you into a form that is unlike your original form (subject to GM discretion). If your new form does not cause your equipment to meld into your form, the equipment resizes to match your new size.
While under the effects of a polymorph spell, you lose all extraordinary and supernatural abilities that depend on your original form (such as keen senses, scent, and darkvision), as well as any natural attacks and movement types possessed by your original form. You also lose any class features that depend upon form, but those that allow you to add features (such as sorcerers that can grow claws) still function. While most of these should be obvious, the GM is the final arbiter of what abilities depend on form and are lost when a new form is assumed. Your new form might restore a number of these abilities if they are possessed by the new form.
From that, the logical conclusion is the following:
You and your eidolon were merged together, and therefore both targeted by baleful Polymorph. You failed your saving throw, so you were transformed into a turtle and your eidolon, acting as a suit of armor, merged into your new form alongside you.
Since the eidolon's bonuses clearly depend upon its form (most evolutions rely on a standard "form" chosen at 1st level), you do not gain any benefits for being bound to your eidolon while it is merged with you, which immediately occurs when you attempt to summon it because it is no longer a separate creature from you. Because you succeeded on your saving throw, you can cast any spell that your new form allows, probably anything that does not rely on somatic or verbal components.
Good luck.