Complex sentence: After the Alewives ceased their live performances, he moved to the Twin Cities to continue his theatrical career, where he became the voice of the Best Buy Idea Box on television commercials and also provided the voice for the titular character in Schrab's Robot Bastard short.
Split into simpler sentences: After the Alewives ceased their live performances, he moved to the Twin Cities to continue his theatrical career. McKenna also provided the voice for the titular character in Schrab's Robot Bastard short.