Hi, Fives! (lol, sorry, I couldn't help myself.
) Welcome to EF. I'm Emma, said admin, and I can confirm everything Russ has already said, with a few additions:
Not all Nymphs follow the Sylvan Creed, and some are more dogmatic about the rules than others. We have had a few rogue characters in the past, the most recent being Solstice's
Aella Karakinos. The most important thing to note is that rogue Nymphs don't get access to regular training, which can stunt their growth in terms of their elemental
skills*, and they are shunned by the vast majority of communes. The more extreme may even exile them. A Nymph who lives away from the communes will struggle less (to an extent) because non-Nymphs won't watch her so carefully or take stock of her every action, whereas a commune Nymph or even one who just lives alone in the Fae will struggle more because she'll be under constant judgement. But of course, being away from the commune she's raised in may be its own struggle.
* There are ways to get around the lack of tutelage, such as finding another rogue who abandoned the Creed after she was already trained to serve as a mentor so you can upgrade your skills, but there has to be sign of the struggle in your app and roleplay. Another problem is the bonding itself; if she's known to not follow the Creed before she bonds with her element, very few Sylphs (the priestesses) will go ahead with the ritual. You can get around that if your character either was a Creed follower until after she'd bonded, or at least pretended (well) to be, but it is something to keep in mind when thinking about your character's history and personality.
There are some exceptions to the rule, for instance the
Furies are protector Nymphs permitted to use violence in defence of their commune. They're fairly rare themselves since most communes use Sidhe (male Nymphs) protectors instead, but one option I can see right off the bat is that your character starts out as a Fury (thus gaining the tutelage she'd need to upgrade her skills) and then 'turns' or abandons the Creed later. You could do it slowly over time, corrupting her a little bit with every fight as she discovers she likes killing/harming for no reason (Nymphs are permitted to nourish or take life in the Natural World to maintain the Balance, so killing just for the sake of it would be a new concept to her). Eventually, they'd catch on and exile her. You'd have the option of roleplaying this out (though it is difficult to find RP opportunities for commune Nymphs since they tend to live away from most of the other characters) or have it be her history and introduce her after she's been exiled. (Feel free to ignore this idea, by the way, it just popped into my head as I was writing.)
As for deformities, Russ is right in that their genetic make-up doesn't really allow for physical defects. Nymphs were created when Xanth gave humans a little bit of her blood (hence the inhuman beauty and physical perfection). A possibility is that the mother was somehow injured while pregnant, or maybe got sick with something that affected the foetus. What the resulting defect is would determine how the Nymphs responded. They're xenophobic but tolerant of each other as a rule, so I can't see them shunning a baby for something that happened in the womb. (Outside reactions to a Nymph that's not perfectly beautiful, on the other hand, would be very interesting.
) Scarring from an accident would, again, depend on how the scars were sustained. If she was doing something heroic at the time of the accident, they'd treat her as a hero no matter what she wound up looking like, but if she was doing something 'wrong' then you enter into the whole "You're not a Nymph, get out!" struggle again. Though, I expect there would be quite a few individuals who just couldn't stand looking at her scars regardless.
Sorry, blathered on a bit there, but I hope it helps give you some ideas. Let us know if you need any help or want to discuss options.