Fan Casting ''The New Guy'' in Arkham Asylum (Season 4)

In the Mid-Credits Scene for the Season 4 finale, Clark is eating lunch with his family and many other Arkham inmates, when the alarms in the prison start going off. Kal-El then hears the gates opening, and sees the guards escorting a new prisoner to his cell. He doesn't get much of a glimpse of the new prisoner, but briefly sees the man is wearing clown makeup overtop of a disfigured human face, destroyed most likely by nuclear radiation.