I don't mean to be scathing or anything, but the hard truth is necessary if you expect, as it seems, to put this into a product. Read this and seriously examine your material afterward. If you want to get something published, be professional about it......... *sigh* That means putting forth an actual effort and being mature about it, for instance.
1. In the Limits of Shapechanging section, when you mention a limitation on organic forms only, you should change the part about carbon/silicon/energy-based creatures to say that in a modern or futuristic setting, the shapechanger cannot assume the forms of creatures not based on the same element, i.e. a carbon-based creature like a human cannot shapechange into a silicon- or energy-based alien, and a silicon-based alien could not shapechange into a human, for example.
2. In Shapechanging 101, you should clarify the 'natural animals only' part, as you use doublespeak there and basically say the character can become anything that isn't a construct, undead, or outsider. So are they limited to the Animal creature type, or not? Clarify. For modern and futuristic settings, you should also clarify whether or not they can assume the form of genetically-engineered creatures (such as the Moreaus in D20 Modern, or genetically-engineered animals or the like).
3. You should note that CR isn't always a great measure of what a player character should be able to assume through shapechanging, though given the restriction you have against using a form's magical abilities, it's not too far off. Remember there is a difference between Challenge Ratings and Effective Character Levels. As for assuming a form, you should know that a DC 10 skill check is terribly easy to succeed at, even at low levels; 4 ranks and an average ability modifier of +2 at 1st-level will ensure that they succeed 85% of the time, bad dice rolls or no, there is no way they will fail more than once or twice in a row, and only be rolling an absurd series of natural 1s, 2s, and 3s on the d20. DC 15 is used in the D20 System as the standard for slightly-difficult-but-not-challenging checks and such, FYI. Also, wizardress is not a word. Use wizard, witch, or sorceress instead; wizard is not necessarily a masculine word, it is nearly as often used to describe female magic-users. You should note in the examples for the Process of Shapechanging that a character could assume the form of a parrot, raven, or the like and be able to cast spells with verbal components, since those forms can mimic human speech (the only limit on that naturally is that those animals lack the brainpower to talk, only to mimic; but since the shapechanger retains their own mind, they could easily speak normally in such a form).
4. Again, DC 10 is terribly easy to succeed at with a skill check. Partial Forms are no more difficult than full animal forms according to your descriptions, though your document says (with no apparent backing) that it's supposed to be more difficult. As for the Limits of Physicality, you don't specify whether or not taking such partial forms as, for instance, the wings of a hummingbird, replaces the character's arms or not, since for birds, their wings are also their only arms. Does taking the tail of a shark replace your legs or not? Does taking the tail of an electric eel, and does that also give you the eel's natural electric capabilities? Does taking a viper's jaws or a stingray's tail allow you to poison enemies with these natural weapons, or do separated parts of your form (i.e. venom, blood, severed limbs) revert to their normal/harmless original form ALA Polymorph Self?
5. In the Making New Forms section, you leave out mentioning the shapeform skill check, you just said a "DC10+5 for every base animal"; fix that. You do not mention if the XP cost must be paid before the skill check, or if it is only paid upon successfully learning the amalgamated form. You also do not state clearly that the new form does not count towards the limit of base forms known. Lastly, your example of a 5th-level character knowing no more than 3 new forms does not include mention of the +2 core/key ability modifier that you mentioned earlier for a different example, which could confuse or mislead. Based on the description of this, BTW, I assume that 'immediately' means that a new form can be changed into with a mere free action at any time, provoking no attacks of opportunity, because you fail to describe it clearly.
6. The section on Permanent Shapechanging is horribly, woefully, inexplicably unclear and nonsensical. Let's see.......for one thing, it apparently costs no more XP to assume a form permanently than it costs to simply learn a new form. Can the shapechanger somehow learn their original form as one of their known forms, in order to return to it if desired? Sure it won't be their base form anymore, but would they still be able to take their original form as a new form known or something? Now, what's with the whole library of forms deal mentioned in the Permanant Shapechanging description? It is gibberish and makes no sense. Serious clarification needed. For instance, does the shapechanger learn a separate library of forms they can assume permanently or something, which they must learn anew and separate from their previous library, or what? Because that's what it seems like based on your gibberish description. What's the deal with eliminating something from the library of forms mentioned in the Permanant Shapechanging description? I suppose the shapechanger can go to the trouble of devising a custom new form (ala Making New Forms) that combines a bunch of useful abilities, then make that their permanent base form with ease? And so on and so forth, this section in your document is hideously unclear and incomplete. Oh, and am I to assume that any shapechanger, even one with only the Skinchanger feat, can assume a permanent form?
7. Shapechanging feats........hrm. For reference, by the way, you really should be capitalizing the first letter of each word in the name of a feat, skill, or creature type, as that is common format for the D20 System, and it makes things more clear. The Normal line for Skinchanger gives the impression that a character cannot take the feat, because it says normal characters cannot become shapechangers, and far as I know, that would mean only characters given the feat as a divine blessing from a deity could conceivably have it.......? Skinchanger doesn't mention what exactly it does for the character regarding shapechanging, it only mentions cosmetic changes, but doesn't describe if that's all or what exactly minor cosmetic changes consist of. I would have to assume, by the description, that a character with Skinchanger as a feat could easily Disguise themselves as anyone by changing their facial features, skintone, hair, pointy ears, scaly skin, canine ears, orcish snout, (get the picture?) and such on a moment's notice, no problem, no Disguise check, Disguise bonus or penalty, etc. I could even assume that these cosmetic changes bring with them the obvious benefits, such as the natural armor of gaining scaly skin or something, for instance, because you are so very unclear in your description.
8. Why does Animal Forms, Animal Empathy, and Fast Change says TYPE OF FEAT in brackets next to the name, and the feats following them say nothing like that....... I assume you just forgot to put the General or Shapechanger or whatever types in these spots? The prerequisite for Animal Forms states they need shapeform at 5+, but it doesn't say what it must be 5+ of. Ranks? Total bonus? You have to be clear on such things.... Animal Empathy is rather unclear what the -2 affects, and of course, you never mention if the shapechanger is even able to communicate like an animal of their current form, as it would be hard to get along with other animals of the sort if you couldn't respond properly to their barked/growled/chittered/hooting/clickin/hissing/etc. communications (mind you, this is quite different from the Speak With Animals spell, which treats them as having more intelligence/awareness than they really do). Oh, and in Animal Empathy's description, it should be spelled subterfuge, not subtrafuge. There are free online dictionaries you can use if you need to, y'know, like onelook.com or dictionary.com.....
9. There's an empty Special: line under Fast Change. The Partial Form feat is terribly unclear, as with the Partial Forms description earlier in the document. The feat also mentions some instant change feat, but I see no such thing in the document. Partial Form doesn't mention requiring Animal Forms, but that should be a prerequisite, not Skinchanger, because Skinchanger is not the feat that grants animal forms from which to gain partial forms. Size Mastery should likely require the Animal Forms feat, since the Skinchanger feat doesn't seem to grant size-altering capacity with its, ahem, undefined 'cosmetic changes only' restriction. New Form is another feat that mentions some nonexistent 'instant form' feat.
10. Mastery of Form not only uses completely different terminology in its description, but is also slightly unclear even to those of us who can understand the gist of it anyway. Shapeheal is a worthless feat, it heals so little damage and costs an action point, and is useable only once a day.....if not for the once a day limitation it might be somewhat useful, but then that depends on what system you're using, because action points differ in each system; in D20 Modern you get a few action points each level, while Spycraft or Monte Cook's Arcana Unearthed do it differently, and Eberron does it differently too, etc....get the picture? Clarify. Shapeheal would be more useful if it healed the character of 1 hit point per hit die when they resume their base form after using the shapechanger feats, at no cost in action points (unless they are able to shapechange an unlimited number of times per day, in which case it should cost an action point to prevent abuse).
11. Combine some of the feats to make a more compact list of maybe 4-5 feats. No more than 3 or 4 if you're going to strictly limit the characters specifically to forms of the Animal creature type. Lastly, regarding the Shapeform skill and this whole shapechanging deal in general...... Not only do you fail to list any skill check DCs and specific uses for the Shapeform skill, but you also don't mention if the skill should be exclusive to certain classes, or only useable when trained (that is, when the character has gained ranks in it), nor do you mention if it is a magical effect itself, or if it requires any special inherant talent or special training or anything else (it seems that anyone, anywhere, could suddenly choose to start using the skill, trained or no, and put ranks in it if they felt like it....). What exactly can the skill do? Does it do anything at all by itself, before gaining the Skinchanger feat and such, and which of its uses are available before gaining particular feats? You don't mention what kind of action it takes to use the Shapeform skill, except for the mentions elsewhere in the document (which should be mentioned in the skill itself) for assuming a form, and you don't say what it takes to assume cosmetic changes, or notice another shapechanger, or make a disguise, or what any of it entails. Is a 'shapechanger' anyone who's put ranks into the Shapeform skill, or what? Define things, yeesh! Most importantly.......you haven't even defined what the whole shapechanging thing does. You haven't defined any actual specifics, for Pete's sake.... How often can a character change shape? What action is it to revert to their base form? Does the character even need any shapechanger feats to do so? How long does a shape last anyway, since you obviously made mention of permanent shapes, but didn't really mention the duration of other shapes? Is there any way for an opponent to dispel or otherwise undo the shape-changing? Is it magical or not, to where an Antimagic Field or such suppresses the change (thus returning them to their base form until they leave the antimagic area)? Is it supernatural or spell-like or anything? Can it be suppressed briefly by dispelling, like a supernatural ability? What exactly does the character get from their shapechanged form? Be specific! What do they get from partial forms, new forms, et cetera?! What stats and abilities of their own do they retain when they change shape? What do they give up when they take partial forms (i.e. does a half-orc lose darkvision when they get the eyes of an eagle)? All in all, very unclear, horribly lacking in specificity, unplayable, and overpowered. I do hope this is only the very first iteration out of several dozen that you'll be working on this, or else I'll be stupified if this becomes part of some kind of D20 product in anything resembling its current state.
Sidenote, I think I'm going to have to modify my Sig at some point, to point out how people really need to get on the ball and learn their basic grammar/spelling and the basic rules of whatever they're working on, or else they'll never be taken seriously and never make any money off their work..... *sigh* I shouldn't have wasted 1.5 hours on this post, but somebody has to do the damned editor's job..... My time better not had been wasted in a merely vain attempt to reinforce grammar/spelling and basic D20 rules comprehension.
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