Here's what I've done thus far. I'm still uncertain whether to make the transformation at-will (like it was in 4e), whether the hybrid form really needs to gain anything unique, or whether the spellcasting bit is too much (I hope not, because it reinforces the shapeshifting theme of the legends).
Hengeyōkai
Hengeyōkai is a collective term for several races of intelligent, shapeshifting animals. The most common hengeyōkai races include badger, carp, cat, crab, crane, dog, hare, monkey, raccoon dog, rat, and sparrow. Posited by some scholars to have originated as fey spirits that fled the Feywild long ago, hengeyōkai are common to the lands of Kara-Tur.
Viewed as carefree pranksters or duplicitous trickster spirits by outsiders, hengeyōkai tend to see life as being as changeable and mutable as their physical form and often find themselves at odds with more hidebound and traditionalist-minded individuals. Most hengeyōkai gravitate towards the fringes of human-settled lands where they can easily go unseen and unnoticed by others. The more sociable, and usually more daring, make hidden communities within the midst of urban centers—showing only their human face to strangers while maintaining their true identity in private.
Even still, hengeyōkai are quite capable of putting down roots and forging deep connections. Tales tell of deep friendships causing a hengeyōkai to take on the role of the protector of a family or small community after they have outlived their friend. Or, conversely, a hengeyōkai spurned likewise holding a grudge for centuries, taking their frustrations out on the descendants of their ire.
Hengeyōkai can live to be over 700 years old. It is said that some races of hengeyōkai grow another tail for each century they live, but this isn’t universal.
Hengeyōkai Traits
As a hengeyōkai, you have the following racial traits.
Creature Type. You are a Fey.
Size. You are Medium or Small. You choose the size.
Speed. Your walking speed is 30 feet.
Darkvision. You can see in dim light within 60 feet of you as if it were bright light and in darkness as if it were dim light. You discern colors in that darkness only as shades of gray.
Animal Form. Choose an animal form when you select this race: badger, carp, cat, crab, crane, dog, fox, hare, monkey, raccoon dog, rat, or sparrow.
Fey Trickery. Starting at 3rd level, you can cast the disguise self spell. Starting at 5th level, you can also cast the alter self spell. Once you cast either of these spells with this trait, you can't cast that spell with it again until you finish a long rest. You can also cast these spells using spell slots you have of the appropriate level.
Intelligence, Wisdom, or Charisma is your spellcasting ability for these spells when you cast them with this trait (choose when you select this race).
Language of Beasts. While in your animal or hybrid form, you can communicate with beasts of your animal form’s type. In human form, you can understand the communication of such beasts, but cannot communicate with them.
Nature’s Mask. As an action, you can change between your human, Tiny animal, or hybrid form. The new form lasts until you change forms again. Your statistics, other than your size, are the same in each form. While you are in human or animal form, other creatures can attempt to discern your true nature by making a DC 18 Wisdom (Insight). You revert to your hybrid form if you die.
While in animal form, you can’t cast spells, and your ability to speak (except to communicate with other animals of your type) or take any action that requires hands is limited to the capabilities of your form. Any equipment you are wearing or carrying in Humanoid form melds into the animal form. You can't activate, use, wield, or otherwise benefit from any of your equipment.
You gain the following benefits while in your animal form.
Badger: You gain a burrow speed equal to half your speed.
Carp, Crab: You gain a swim speed equal to your speed, and then your land speed becomes 5 ft. You can breathe underwater.
Cat, Monkey, Raccoon Dog, Rat: You gain a climb speed equal to half your speed.
Crane, Sparrow: Your land speed becomes 5 ft., and you gain a fly speed of 30 ft.
Dog, Fox, Hare: Your speed increases by 10 ft.
You can use this trait a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.
