This has been one of my favorites since I was a kid. The machinations that Mysto the Magician goes through to upstage Poochini are hilarious. Notice the hair on the film gag? My favorite change is the one near the end where Poochini's a Polynesian (?) dancer and the two rabbits are beside him! One word of warning though - On Cartoon Network, they have cut three of the changes (Chinese, both Blackface) so it's not as good as the uncut version.
Review of Magical Maestro
