It would be much simpler if it worked the way you say Jackstand:
QUOTE (Jackstand @ Jun 13 2008, 12:00 AM)

Let's try this again and start from scratch.
...
So...
1. Immunity to Normal Weapons applies to all non magical attacks.
2. Some critter powers are natural and some are magical.
3. Those critter powers which are natural are not magical.
4. One power, Natural Weapon, grants claws.
5. Claws are a natural power.
6. Natural Weapon is a natural, and not a magical, power.
7. Those Critter Powers which are magical in nature bypass Immunity to Normal Weapons.
8. Those Critter Powers which are natural in nature do not bypass Immunity to Normal Weapons.
9. Natural Weapon does not bypass Immunity to Normal Weapons.
Any further questions?
Unfortunately, the way the text is written, we are in the section on "Powers". The description of the Immunity power specifically says that Critter Powers bypass Immunity to Normal Weapons. Many critters clearly have the "power" Natural Weapon. Therefore, the book as written is quite clear that Natural Weapon is a power, and that all critter powers bypass this Immunity.
Yes, one solution is to simply say, as every GM has the right to, that this is wrong, and non-magical critter attacks shouldn't bypass armor. I might even personally agree.
But I am trying to understand how RAW is supposed to work in this regard.
In particular, is there some reasonable model by which a GM who is trying to follow RAW, who has some non-listed animals confronting spirits, can decide whether those animals have "Natural Weapons"
We know that the hooves of a horse don't count. (Even though they are as effective as most clubs.)
We know that the bite of a common dog does count for this power.
But we don't know about Bear Claws, Boar Tusks, Hippo teeth, Rhino Horns, Elephant Trunks or Tusks, ...
NOw, I don't want Catalyst trying to list every possible animal. It is a waste of time.
That is why I am asking what the theory would be, if one was trying to follow RAW, as to which animals have Natural Weapon, and which do not. (I have real trobuel telling teeth from hooves for this purpose.)
Joel