Complex sentence: Clokey moved forward, producing a pilot featuring the character Gumby, which derived its name from the muddy clay found at Clokey's grandparents' farm that his family referred to as "gumbo".
Split into simpler sentences: Clokey moved forward, producing a pilot episode featuring the character Gumby. The name "Gumby" came from the muddy clay found at Clokey's grandparents' farm that his family called "gumbo".