Story
Featuring
Superman and Batman
Storyline
The super-sons' adventures are revealed to be computer simulations observed by Superman and Batman. But when Superman leaves the program running, Superman, Jr. figures out that there is another plane of existence, and the boys enter the real world. There, their presence causes natural disasters, so they sacrifice their artificial lives.
Story Notes
That the Super-Sons were actually computer simulations was previously mentioned in The Superman Family (DC, 1974 series) #192.