Home / Detective Comics (1937-) #316
�DOUBLE BATMAN VS. DOUBLE X!� Simon Ecks escapes from the sanitarium he was locked in with his memory restored. Ecks decides to develop another duplicator device and becomes Dr. Double X once again. He matches wits with Batman again, although this time, Batman is able to defeat him by generating an energy duplicate of himself with Ecks� machine. Baman fights Ecks while their respective duplicates fight each other.