Continuity mistake: After Lois and Jimmy get in a helicopter, the scene changes back to Doomsday and Superman fighting on a street. As Superman is attacking Doomsday, there is a yellow car in the street behind the creature. Superman then gets a few good hits off, and sends Doomsday flying backwards through the air. Suddenly the yellow car has turned into a large 18 wheeler truck. (00:19:40)
Continuity mistake: Doomsday picks up a tank and throws it at a group of solders. There is a star on the back fender of the tank that is just the outline of a star. But when Superman catches the tank, the star is solid black. (00:17:50)
Continuity mistake: On the bridge, Doomsday crushes the skull of a soldier with his hand. Burning rubble and debris are shown behind him. After one of the solders turns the 50 cal on Doomsday, another shot shows a red car suddenly appears behind Doomsday. The double yellow lines also suddenly vanish from under Doomsday. (00:17:10)
Continuity mistake: As Lois and Superman are having their first argument about him telling her who he really is, there is a pink stone like thing in the room with them. They are standing in one spot in the scene, but the stone keeps moving around from shot to shot. Most noticeably at the beginning of their argument, and the end of it when she is walking away mad. (00:13:35)
Continuity mistake: After Superman finally reveals to Lois that he is Clark, she tackles him against the wall and kisses him. When his head hits the wall behind him, it knocks a picture loose that tilts sideways but is right behind his shoulder. When the angle changes to a closer view, the picture has moved almost totally off screen and barely a corner behind Clark's shoulder. Then a moment later, without them moving, it shows a side shot again and now, they have suddenly moved further down the wall, and more away from the wall. The picture being further away, and the stuff in the background moving closer. (01:13:40)
Continuity mistake: After Dark Superman finishes destroying all the Supermen clones, he punches and destroys the console that controls the room. The camera pulls back and shows the incubus fluids completely covering the ground and some dead Superman clones close by. But then when Dark Superman begins walking away after telling Jimmy and Lois to evacuate, there is suddenly much less incubus fluid on the ground, the dead Super clones change position, and some gray mud like stuff appears on the floor. (00:59:30)
Continuity mistake: After Lois and Jimmy discover the room full of Superman clones, Jimmy begins snapping pictures. Then Lex shows up and holds them at gun point. When Lois and Jimmy begin backing away, Jimmy is on Lois' right side. Then suddenly between shots, they switch places. (00:58:05)
Continuity mistake: When Lex finally wakes back up and confronts Lois and Jimmy, he holds them at gunpoint while walking between a row of Superman clone incubation chambers. Every time it shows Lex from a different angle, he is in a different position in the row. Sometimes in the center, sometimes on one side, and then the other. (00:58:00)
Continuity mistake: After Lex realizes Lois and Superman were lovers, he sits down and tries to seduce her and says "You need someone to take his place... Someone strong." He places his hand on her chin to turn her head. Between shots and the close up, her lips are closed, and then suddenly open showing her teeth. (00:55:10)
Continuity mistake: As Dark Superman begins sitting down at a mirror in the salon, there is a green bottle on the desk with a black cup next to it. Then after he sits down, the black cup suddenly becomes a red bottle. (00:53:05)
Continuity mistake: As Dark Superman walks from the door of the salon to an empty booth, he walks in a straight line and passes two mirrors and booths where people are getting a haircut. When it cuts to a different angle, there is only one booth behind him. One of the ones he passed has vanished. (00:53:00)
Continuity mistake: When Dark Superman goes to the door to the salon, the door has on it the number 932. He opens the door in, and it swings to the right. But it cuts to an inside view and suddenly it is swinging it to the left, and the font of the number has completely changed. (00:52:50)
Continuity mistake: As Dark Superman walks into Lex's office, Lex turns his head sideways and looks at him as he says "Well... The piratical son of Krypton." It cuts to a close up from a different angle and suddenly Lex is looking straight forward. (00:51:40)
Continuity mistake: When the real Superman is in the solar chamber going through accelerated absorption of solar energy, there is a giant, dormant robot to the right of the chamber, and Superman is on the left side facing it. A few shots later, suddenly Superman is on the same side of the chamber as the giant robot and has his back to it. Then in the very next shot, Superman is instantly on the left side again facing the robot. (00:51:30)
Continuity mistake: As the police car with Toyman in it arrives at the police station, there are 5 cops standing at the bottom of the steps in front of the station standing it two groups. Three side by side, and then two off to the side. There are also several civilians close to the steps. Then it cuts to a bird's eye view of the station and suddenly there are only 4 cops in front of the station, and their arrangement has changed. And the civilians around the station are suddenly much further away from the steps. (00:48:00)
Continuity mistake: Dark Superman comes and takes Toyman from the cops. As he does, the police car is a good distance behind them. Then the shot shows Superman take Toyman up in the air, then back to the cops. Suddenly the police car is right behind them by just a few feet. (00:48:15)
Continuity mistake: When the police show up to try and arrest Dark Superman, the overhead shot of the cars spotlighting him show him by a building, but approximately 10 feet away from it, give or take a few. He is also about 5 feet away from the old lady. Then when the cops get out and walk up, it shows Dark Superman again from a different angle, and suddenly he is only a few feet away from the wall, moved closer to a balcony like thing, and is now just a step away from the old lady. (00:50:55)
Continuity mistake: When Dark Superman is confronting the old lady about letting her cat out, police cars drive up and spotlight him. Dark Superman's shadow is cast on the wall beside him, and on the small balcony. But when the camera angle changes, his shadow is on the bricks, not close to the balcony. (00:50:45)
Continuity mistake: As Lois makes her way to the scene where Toyman was killed, there is a green sheet over his body on the police car. There is blood going from his exposed hands down the side of the car to the ground, but there is no blood on the top of the sheet. Then when Lois sees Jimmy snapping pictures of the scene, there is suddenly quite a bit of blood on the green sheet. Then when the camera shows a high angle of the vehicle with the dead Toyman on it, the blood is gone once again. (00:49:10)
Continuity mistake: The live news broadcast of Superman's interview after his resurrection shows it broad daylight in Metropolis. When Martha Kent sees this at her farm, although being in the same state, it is pitch black night time outside at her house. (00:40:10)
Chosen answer: When they call Doomsday a machine, they don't mean a literal machine. Just that he was built/designed. The comics were much the same. Doomsday was created by placing a baby on the most dangerous planet in the universe, and cloning that baby every time it died, forcing it to adapt. Doomsday eventually escaped this torture.
MasterOfAll