Note: permanent magical effects are still magical and can be dispelled.
Saves with "diminishing returns" cause penalties for repeated failure. Typically, a save to end is allowed every round. With diminishing returns, the first failure delays the next save until the end of the encounter; if that fails, the next save is the end of the day, and if that fails, no further saves are allowed.
Creatures polymorphed out of their original type (e.g. humanoid -> animal) lose all natural abilities of said type (e.g. humanoids -> animals lose the power of speech, opposable thumbs, etc), but gain natural abilities of the target form.
Polymorphing magically makes clothes and worn items disappear for some reason. This is kind of dumb. DMs can opt out of this.
Rank 1
Animorph: At-will, std, ranged; subject is polymorphed into a harmless animal, Cha ends. Can use on self as a concentration effect.
Alter Form: At-will, std, touch, sustained; willing subject's form is altered to suit their specifications, within the normal bounds of their type. For instance, you can make a medium humanoid look like any other natural medium humanoid. You can even grant them abilities they do not normally possess, but are possible within their type (for example, a human might gain the gills and flippers of an aquatic humanoid, or the feathers and wing membranes of an avian humanoid). The subject sustains the effect with their own concentration.
You can use Alter Form against a hostile target, but they are allowed a Cha save to end. You cannot make the target unviable (e.g. cannot remove ability to breathe oxygen from a creature currently in an above-water environment), but you can give them average ability scores and remove all extraordinary physical features.
Rank 2
Augmentation: gain a single cool ability from another form without changing your current one (e.g. breath weapon, flight, etc). TBI
Polymorph: At-will, std, ranged; you change the subject's form into a creature of equal or lesser CR. If hostile, Cha ends.
Feats
Permanent Polymorph: Your hostile polymorphs gain "diminishing returns" to their saves, and can thus become permanent.