Moon Knight (1980 1st Series) #12

"The Nightmare of Morpheus!" Written by Doug Moench, with art by Bill Sienkiewicz. Cover by Frank Miller and Al Milgrom.

Marlene's brother is put into a coma by one of his psychiatric patients who gained super powers when he lost the ability to dream during sleep; Moon Knight tries to stop the monstrous villain before he can return to finish off the good doctor.