Merlin the Magic Mouse debuted in his self-titled first short, released just before Thanksgiving in 1967. Daws Butler gave Merlin a voice like that of W. C. Fields, but it certainly wasn't the first time Fields had been the inspiration for a WB character. Second Banana, Merlin's sidekick, gets Butler's oft-recycled Elroy Jetson/Augie Doggie voice. However, in subsequent shorts, Butler was replaced by Larry Storch (ex-F-Troop), and Second Banana was given a redesign, making him slightly bigger in size.
Let's take a look at "Merlin The Magic Mouse":
Is it any wonder that Merlin and the other rookies of this era (Cool Cat, Bunny & Claude) weren't brought back in later years?