Lilo & Stitch: The Series (2003)

S2E17 Phoon

Experiment 540, known as PHOON, is set loose just as Lilo decides to leave her experiment-chasing days behind and enroll in Hula Hip Hop Fusion school. The chaos begins when Gantu suffers a head injury from the rampaging creature. Meanwhile, Jumba's latest invention accidentally transforms Phoon into a colossal beast. Gantu, disoriented, starts to believe that characters like 625 and Hamsterveil are merely illusions of his mind.