The Ultimate Book of Spells - Season 1 - Eps 12: Out of Shape
Zarlak has captured small beings called ""the tricky trolls"", but one escaped and come to the kids. Zarlak then send his dragon to steal their magic book, but took Verne (who turned into into UBOS) instead, then they kidnap Gus, leaving Cassy to save the day, who is having a hard time using her shape-changing powers. Will she be able to save the day by turning into Zarlak?
About The Ultimate Book of Spells

Title: The Ultimate Book of Spells
First Air Date: 2001-09-12
Last Air Date: 2001-12-05
Status: Canceled
Rating: 6.5/10 (from 2 votes)
Language: EN
Seasons: 1
Total Episodes: 26
Network: CBBC YTV Toon Disney
Genres: Animation, Sci-Fi & Fantasy, Family, Kids
Production Companies: BKN International
Synopsis
Inspired by the popular Harry Potter book and movie series, the show presents a trio of "wizards-in-training" at an enchanted private school run by Miss Crystalgazer. Cassy is a junior witch, Gus is a half-elf/half-human junior wizard, and Verne is a promising "mortie", i.e. a non-magical human. With the guidance of the talking Ultimate Book of Spells (aka UBOS), the three have to battle the evil wizard Zarlak, who's trying to steal all of the world's spells.
Cast

Ron Halder
UBOS (voice)

Janyse Jaud
Cassy (voice)

Cathy Weseluck
Vern (voice)

Michael Dobson
Prince Erbert / Snap the Dragon (voice)