Complex sentence: Apps's numbers declining, he was traded to the Los Angeles Kings in the 1977-78 season and retired two years later, finishing his career as the Penguins' career assist leader and second in goals and points.
Split into simpler sentences: Apps's numbers declining, he was traded to the Los Angeles Kings in the 1977-78 season and retired two years later. He finished his career as the Penguins' career assist leader and second in goals and points.