Continuity mistake: As Superman is throwing Doomsday at a small power station, you can see several cars out in front of it on the two lane road. Notably on the left side a small truck in the middle of the road, that's not moving at all, and a small pink sedan car right on the edge of the sidewalk. But only a few seconds later as Doomsday runs through the fence back in the other direction carrying Superman, suddenly the truck has vanished, and the pink car has changed to a brown station wagon and is facing the other direction. The two lane road is now a three lane road, and the sidewalk next to the fence is suddenly much more narrow. (00:22:15)
Continuity mistake: In the first shot it is seen, the fence of the power station that Doomsday is thrown at shows that gate part is slightly taller than the rest of the fence and has one sign on each door of the gate. But then moments later as Doomsday is plowing through the gate, it is now the same height as the rest of the fence, and only one sign is present, which becomes smaller and a darker color. Also two vehicles appear behind the fence that were previously not there. Also on the gate there is a sign on each side of it, but before it breaks there is a sign only on the right side. (00:22:30)
Continuity mistake: Just before Doomsday ploughs through the fence of the power station carrying Superman with him, you see down the street he is about to go on that there is a yellow 18 wheeler with gray trailer and an pinkish car on the left side of the street. But then it cuts to a close up of those same vehicles as Doomsday steps on one to jump, and suddenly both have turned into green cars. (00:22:35)
Continuity mistake: After their fight destroys a small power plant, Doomsday grabs Superman and takes off running with him. Doomsday steps on a green car and leaps into the air through the street. As the shot cuts to show him coming towards it, the power plant is shown smoking behind them, but the green car has vanished. Unless it's the car suddenly on fire... In which case the flames instantly appeared between shots. But Doomsday just crushed the roof with his jump, which couldn't have started a fire. (00:22:35)
Continuity mistake: When Doomsday slams Superman down into the subway, the hole they make in the street is right in the middle of a crossing. But a minute later in the film as civilians are walking up to the hole, there are no lines anywhere around it. Moments later after Jimmy takes a picture of the hole, the shot cuts to a far angle and now the hole is next to the crosswalk lines, and in that shot the stairway entrance to the subway station also vanishes. The road also becomes much wider with more lanes, and the red truck turns around. (00:22:40 - 00:23:25)
Continuity mistake: Doomsday leaps into the air and smashes Superman down into the ground, crashing down into a subway station. As they are hitting the floor, you can see the brown columns holding up the roof are almost to the edge of the walkway by the tracks and touches where the tan area of the floor changes to a light green color at the end. But then Superman shoots Doomsday back with his laser vision and Doomsday looks at him angrily, and now the columns have a good few feet between them and the edge of the walk way. (00:22:40)
Continuity mistake: Once Doomsday slams Superman down through the ground into a subway station, he has him by the neck against the floor, and then clasps his other hand around Superman's neck. When he does, Superman looks up at him with his eyes just before he blasts Doomsday away with his laser vision. But his head is still turned sideways. It cuts to a different angle and suddenly Superman's head is fully facing up towards Doomsday. Also the grip in how Superman and Doomsday are holding each other changes a bit, notably with their hands. (00:22:45)
Continuity mistake: After Superman blasts Doomsday away from him in the Subway station, Doomsday grabs him by the leg and flings him to the other side of the tunnel, breaking a large hole in the wall. As he hits, you can see there is a subway exit on the same wall about a yard or so away from where Superman hits. But then when Doomsday leaps at him to continue his attack, the wall is suddenly solid where the exit once was. (00:22:50)
Continuity mistake: Doomsday and Superman leave a sizable hole in the roof of the subway station as they slam in through the streets above. But when Superman throws Doomsday down onto the tracks, the shot shows the same spot where they made the hole coming in, only now the roof is devoid of any damage and the hole entirely gone. (00:22:55)
Continuity mistake: During their fight in the subway, Doomsday throws Superman through one of the red support columns. But in the shot where Superman throws Doomsday onto the tracks, all the columns are in perfect condition. (00:22:55)
Continuity mistake: When Superman throws Doomsday onto the subway tracks, he slides across them and breaks the railings. But when Superman dives at him and receives a monstrous backhand slap to the face, which sends him down the subway tunnel, the reverse shot showing Doomsday has him standing on subway rails in perfect working order and condition. (00:23:00)
Continuity mistake: Once Superman throws Doomsday down onto the subway tracks, he flies at him and Doomsday back hand slaps him hard down the tunnel. Superman lands on his face on the rails, and you can see the sleepers on the ground under the rails. When the camera changes angles as Doomsday approaches him, the sleepers suddenly become much larger. (00:23:05)
Continuity mistake: When Doomsday backhand slaps Superman down the tunnel, Superman skids along the roof for a moment first, and leaves a good amount of damage to it in the process before he falls to the rails below. But then when the subway train is coming and Doomsday turns his attention to it, the damage Superman made to the roof of tunnel has completely fixed itself. Also some of the lines at the start of the tunnel dividing the different concrete slabs have vanished. (00:23:10)
Continuity mistake: As Superman tackles Doomsday out of the way of the subway train, you can see that Superman grabs him from behind and is pushing him towards the wall, Doomsday facing it. But then it cuts to a different angle just before they hit the wall and suddenly Superman has Doomsday by the front and Doomsday's back hitting the wall. (00:23:15)
Continuity mistake: Jimmy and Lois walk up to the hole in the ground left from where Doomsday smashed Superman down into the subway. Jimmy holds up his camera and takes a picture, then it cuts to a close up of them. Suddenly his right hand goes from holding the side of the camera to holding the lens, and the strap of the camera is suddenly over his arm. Lois and Jimmy are also suddenly closer together, and her arm goes down to her side. (00:23:30)
Continuity mistake: When Superman is launched out of the ground from his fight in the subway with Doomsday, he smashes into a brown building with yellow windows. The windows on the left side of the building are in a tall vertical column, with several horizontal rows of yellow windows on the rest of the building. When Superman hits the building, you can see he hits between the area of two horizontal rows of yellow windows. But it cuts to a close up and suddenly he is lined up with one of the rows. (00:23:35)
Continuity mistake: After Jimmy takes a picture of the hole in the ground above the subway station, the shot pulls back and shows the hole, with several people gathered around it and some cars. Then suddenly some of the road is pushed up from Doomsday and Superman fighting below and the people turn to look. The angle then changes before more road is pushed up on the other side of the hole, and suddenly the part of the road that was pushed up in the previous shot is back down to normal, the green cars have vanished and a white one appears next to this new pushed up spot, and a guy wearing a white shirt suddenly appears where the road is pushed up. Also the crosswalk lines once again vanish. (00:23:35)
Continuity mistake: After Superman is flung out of the subway and hits a building, then lands on the ground face down, Doomsday leaps out of the hole and you can see what appears to be a brown 80's SUV, or a truck with a camper, behind him next to some civilians. The camera angle changes a side shot of him as Doomsday turns his attention to the civilians and charges them, and now the SUV has vanished. (00:23:40)
Continuity mistake: After Doomsday and Superman get out of the subway, Superman flies into him before the monster attacks more civilians. But Doomsday counters and smashes Superman into the ground. Superman is then trying to get up and is on his hands and knees. But the angle changes and suddenly he is on his side. Also the car beside Superman vanishes between shots. (00:23:45)
Continuity mistake: Doomsday has a bone spike protruding up from each of his 4 knuckles. But when Doomsday grabs Superman by the head and draws back to punch him hard in the face, the spike on his thumb is missing. Superman catches his fist, and in that shot you can see two more of the spikes have vanished, and Doomsday only has one over his middle knuckle. (00:23:55)
Answer: In the comic book, Doomsday was put in a strait-jacket, strapped in metal bondage and placed in a cube like metal prison buried deep in the earth. It took him centuries just to break the bonds, then spent more centuries just punching his way out. With earthquakes, volcanoes and other natural disasters those events could shift Doomsday's prison to the surface.