So I wrote this class feature for my Necromancer class, but it's kind of buried in that giant wall of text so I thought I'd give it its own thread for feedback and pointing out where I done fucked up. Basically the idea is to give you a class feature that lets you adopt the form of other creatures in a way that remains balanced without resorting to a standardized list of bonuses, penalties, and miscellaneous qualities. So with that brief introduction, I've genericized it to an ability that can be used for any class that shapechanges.
EDIT: The class feature as written does presume that you expend a spell to activate it (it should be a spell of your highest or 2nd highest level in standard Vancian casting), and also that you use a system wherein you have a caster level that is fixed at the sum of your spellcasting classes + 1/2 your other classes. There's no real way to genericize that out of the ability without changing the balance, at least that occurs to me right now.
Change Shape (Su): At X level, a <class_name> learns to manipulate her own body, taking on aspects of the creatures she reveres. As a standard action, she can assume the form of a [list creature types here*] of her size or one size larger or smaller than she is by expending a spell as if it were cast. She can remain in her new form for as long as she likes, and can return to her normal form as a standard action or expend another spell to assume a different form without having to first return to her normal one.
She takes the form of an average creature of that kind, even if the particular example with which she is familiar is extraordinary in some way. She can only assume the form of a creature whose form she has learned. To learn a creature's form, she must either make a Knowledge check as if identifying the creature or have personally encountered the creature during play. Once either of these conditions is met, she can meditate on the creature's shape for 1 hour to learn its form. She can learn as many forms as she likes, so long as their total number of hit dice does not exceed twice her caster level and no single form has more hit dice than her class level. She cannot learn the form of a template or templated creature as a general rule, but she can learn the forms of [list specific templates here, if your class's flavor requires them, such as Skeletons or Zombies for the Necromancer] creatures of a particular kind. Whenever she gains a level, she can choose to forget any number of forms, allowing her to replace them with others.
- Any equipment carried by the <class_name> melds into her new form and becomes non-functional for the duration of this ability. Any equipment she dons in her new form likewise melds into her when she leaves that form, and remains nonfunctional until she again adopts it. She cannot speak unless the creature whose form she assumes can normally speak, nor can she carry or use items that the creature whose form she assumes could not. She can make sounds that a normal, untrained creature of the kind whose form she has assumed could make, and communicate with others of that kind to the same extent as any other untrained creature of that kind.
- She retains her normal type and subtypes, but if her assumed form had the aquatic subtype, she gains it. She does not lose it if she has it normally and she assumes a form that does not. Her size changes to that of the assumed form.
- She loses her natural weapons, natural armor, and movement modes. She gains the assumed form's natural weapons, natural armor (to a maximum of ½ her caster level), and movement modes.
- She loses all of the special qualities, special attacks, and other traits of her normal form, including class features, such as spellcasting, except for her Apotheosis abilities and the Change Shape ability itself. She retains her feats, even if she would not qualify for them as a consequence of adopting a new form. While she loses her spellcasting ability, she retains her spells per day allotment. She gains the special qualities, special attacks, and other traits of her new form. She does not gain any spellcasting, manifesting, maneuvers, or similar abilities** of a creature whose form she assumes. Because her type does not change, she does not lose the traits of her original type, or gain those of her new type.
- She replaces her normal ability scores with those of her new form, each with a maximum equal to 14 + her caster level. If the form she would assume would have a nonability, she retains her normal score in that ability instead. Her alignment, personality, and motivations remain the same, but because her mental ability scores may change, her ability to pursue her goals and make effective decisions may be impaired or enhanced. Modify her statistics according to her new ability score modifiers.
- She is camouflaged as a creature of the kind whose form she has assumed, but because she retains [list any specific class features she retains here], she stands out among them. She gains a +4 [change to +10 if she doesn't retain any class features, and reword the previous sentence appropriately] bonus to Disguise checks to appear as a normal creature of that kind, and takes penalties for attempting to disguise herself as a member of a different race, gender, and so on as if she were actually a creature of the kind whose form she has assumed. Even somebody who penetrates her disguise only deduces that she is not what she appears to be, and does not discern her true form unless benefiting from some special ability that displays the true form of a shapechanger.
Other than described above, she retains all other statistics of her normal form, including hit dice, base attack bonus, base save bonuses, skill points, and so on.
At Y level, she expands her repertoire, and can assume the form of creatures up to two size categories larger or smaller than her. At Z level, she again improves her ability, and can assume the form of creatures up to three size categories larger or smaller than her.
*Keep in mind that different creature types make this ability's power vary. For instance, plants, animals, and undead all tend to have inflated hit dice for their CR, making them fairly low-power choices overall. Dragons are very powerful, but have similarly inflated hit-dice, which probably makes them medium in power. Outsiders often have few hit dice for their CR, sometimes even having a CR higher than their hit dice and access to great powers, so they are extremely powerful choices for this ability and probably should be the central feature of this class.
**"Similar abilities" is a deliberately vague term here, because I'm not sure how to describe in one term all the variant spellcasting systems that exist. The point here is to restrict you to class features that appear in the Special column of a class.[/list][/list][/list]
