>When you choose one of these edges does it override the forms
>you can't receive due to prior forms? I mean, say a person has
>the random shot at 7 or 8 possible forms and only 6 forms due
>to prior received forms, do they then go back to the
>possibility of 7 or 8 minus the one that they just got?

If you've got tortoise as your tier 2 defense form, and you've got mongoose as your tier 1 form, you won't get armadillo when you re-roll because of the pairing with tortoise. You also won't get the form you are roll/spinning from.