I decided to have a kelpie (her name is Kellie!) as the horse instead of a Unicorn/Pegasus since I thought it would be more unique. I will probably switch out Jormungandr too since the Chinese dragon is another massive serpent-shaped creature lol. I will post an update on the poster of the zodiac creatures soon.
Kelpies are aquatic spirits in Scottish folklore capable of shape-shifting, usually taking the form of a horse or human. They will try to charm humans into the waters and drown them. Their skin is adhesive so anyone who touches them will be stuck. They are said to have the power of 10 horses, but can easily be killed with silver bullets, similar to werewolves.