Elizabeth uncorked an empty bottle and filled out with water, then thought for a while before writing 'Cat' on it. She made a wolf bottle too, then had an idea.
She'd always loved mythical creatures, especially the Thunderbird. Writing it on the bottle, she closed the case and reopened it before grabbing the measuring cup and reading the instruction taped to it.
"Pour these amounts to give a certain effect.
Up to the first line gives you the ears of the animal, and the second gives you the tail. Third is fur, scales or feathers. Four is the front legs. If your animal has wings, you'll grow those instead on your back. Five gives you the back legs, and six gives you the head. Pour up to line seven, and you'll become an anthro. The eighth line is the entire bottle, so you'll fully become that animal. Pour, then transfer to another bottle. If you pour to line five, transfer, then pour to line one, you'll get the ears and back legs, not the head. Use this to mix your own potions. Only magical bottles will automatically refill, so write down the recipe."
Elizabeth, to be careful, called the shop and asked for a bottle. When she hung up, there was a new space in the box with a bottle. "Wow," she thought, "that's magic, alright."
She poured wolf up to line two, then added it to the bottle. Then she poured cat to four and five, then thunderbird to five, hoping it'd work. Then wolf to three and cat to six, and wolf to one. The potion complete, she labelled it as "wolfcatbird"in the magic bottle and put it in the box. Closing and reopening it, the bottle was a bright electric blue instead of the greenish brown it was before. Uncorking the human bottle and pouring it into a dish before replacing it in the box, she drank the potion and put back the bottle, closing the box.
The changes were immediate. Wolf ears and tail appeared, ripping her pants. She was surprised at the lack of pain as grey fur sprouted with a white underbelly. She heard a crack as she fell onto all fours, her limbs becoming cat-like, but retaining the fur and strength of a wolf. Elizabeth ran to the bathroom and tried to look in the mirror. Her nose grew smaller as her eyes changed and the fur covered her face, and her lips pushed out and became a muzzle. Her human hair flattened into fur and her human ears disappeared, and whiskers grew on her feline face. She still had the eyes of a wolf. Finally, great blue-feathered wings spread from her back, crackling with electricity. She folded them on her back and went to lap up the human potion, happy (and a tinge horny) at the success of the potion. As she became human, she smiled at the blue potion as she got dressed.
An idea crossed her mind, and she dashed to get a necklace. She had one that was a thick ring of jade on a black string, and she opened the potion, pouring it into a glass and submerging the necklace. After a minute, she removed it. It had drained the potion from the glass! Elizabeth was excited. A strange glow surrounded it, and she put it on as she put everything away. She then closed the box and put it in her room.
She tested it, and focused on the feeling of the changes. Soon, she opened her eyes and found she'd become her hybrid! She focused on being human, and watched as she morphed back. With a bit of practice, she was able to achieve an anthro form, and a human form with wolf eyes, ears and tail, and the same blue wings. In the mostly human form, she tested her wings, and learned how to use the thunderbird's electric powers. By the time Gina got home, she'd mastered her forms, and she shifted back to human as Gina knocked at the door.