At the Community Comic-Con round table this week, Jim Rash said his character of Dean Pelton would be getting an adversary on season three. But he may have said it in a more foreboding tone if he knew the man's identity:
TV Fanatic has confirmed that John Goodman will appear on at least six episodes of the NBC sitcom as Vice Dean Laybourne, the head of Greendale’s air conditioning repair school and an enemy of both the dean and our beloved study group.
Goodman will debut on the September 22 premiere. Michael K. Williams will also make his first appearance on that episode as the group's intense her biology teacher.