Quest of the Therian Urn
As the story begins, the main character, Bob, is given a ceramic urn by his father. In cleaning the urn, he discovers that it transforms whatever is placed inside into some object of delight, be it foods, jewelry, toys, tools, all depending on the tastes of the user. What they do not realize is that there is a terrible price to be paid for using the urn.
At the end of the day, Bob and his four friends are transformed into animals. Trapped in the body of a platypus, Bob seeks to destroy the urn in order to break its evil spell, but finds that this is nearly impossible, as it is a wizard's horcrux (an object containing part of a wizard's soul, enabling him to remain in the world after death, a la Sauron's Ring in Lord of the Rings or the Horcruxes of Lord Voldemort from the Harry Potter series) and is protected by its own twisted power. Thus, the four transformed teenagers, Bob the Platypus, Lucy the Raccoon, Tim the Tiger, Zeta the Wolf and Arnold the Pony set out across the country in a stolen RV in order to find some way to destroy the urn.