Complex sentence: He once accidentally caused a fire that destroyed a pearl given to his father by the Jade Emperor, and was about to be executed for committing this offence when Guanyin appeared and pleaded for his life.
Split into simpler sentences: He once accidentally caused a fire that destroyed a pearl given to his father by the Jade Emperor. He was about to be executed for committing this offence when Guanyin appeared and pleaded for his life.