Rakshasa’s Fortune is a magus arcana that lets you take extra monster abilities, that your selected shape doesn't already have, when you polymorph. See description below:
"Benefit(s) Whenever the magus casts a spell of the polymorph subschool on himself, he can draw a card from a complete harrow deck he owns as a free action.
If the card’s alignment and the magus’s alignment are a true match, the spell’s duration is doubled and the magus can select two additional monster abilities granted by the polymorph spell (such as scent or grab for beast shape II), even if the form assumed by the magus doesn’t normally grant that ability."
My question is what form do these new abilities take? There are no clear rules that I could find, so looking for thoughtful opinions. If you choose poison for a form that doesn't already have poison, is that ability:
1.added to a current natural attack if the form has one?
2.added to a current weapon if there are no natural attacks with the chosen form? (Formian Myrmarch adds poison to weapons)
3.added to a new natural attack that is similar to the poison application of the monster whose poison is being selected?
I am inclined to think it should generally be 3. However nowhere does it say that the arcana gains and extra natural attack.
My preference would be that it is 1. because a poison punch is far cooler than a poison bite.
2. only if the creature has the ability (like formian myrmarch) or the character has something like the Injecting enhancement on a weapon.
Thoughts?
Poison is difficult to handle, because unlike the other abilities, it's not standardized.
My advice:
If poison isn't removed from the options list for being a hassle, allow attaching the poison to any natural attack that the form can only make one of (barring Haste). Gore, bite, sting, etc., but not claws, unarmed strikes, or weapon attacks. The poison should be chosen from a creature that the spell would allow turning into, with a CR capped at caster level. Fortunately, the DC is already covered by polymorph rules. If the form doesn't have any appropriate natural attacks, then it delivers the poison as toxin instead, only when bitten, making it a poor choice.
Alternatively, you might need to select a poison from a creature the spell could turn you into that is attached to a natural (or manufactured) weapon that your chosen form has. Actually, I like that solution better. If you can find a valid poison-punch monster, then you can use it. If you want to wield a weaker weapon like a javelin to get iterative poison attacks, you can do that.
3 is definitely inappropriate. Giving yourself extra natural attacks is outside the scope of the ability.
We are in agreement that poisons selected should be from an actual published creature. I was working under the assumption that any poison picked would need to be a replica of one that already existed in the bestiary. Just picking a random poison, with any attributes could get tricky. I also assumed that no matter what attack the poison was attached to that it would be a stand alone attack, and could be used once in per round (haste type effects as exceptions).
3 is the least interesting but I could see a GM saying "the poison comes from a stinger, so your form grows a tail and can poison using that stinger."
Thanks for your thoughts QuidEst.