Continuity mistake: After the workers at Project Applecore discover Doomsday's ship, Dr. Murphy and the other two stand to look at it. One is standing in front with her adjacent behind him, and the other male worker behind her on the other side. When it cuts to a far shot of Doomsday's ship, suddenly the three of them are in line standing side by side. (00:06:15)
Continuity mistake: After the workers at Project Applecore discover Doomsday's ship, the scene changes to Lex in his office staring out the window. It cuts to a further shot as Tess walks, and suddenly Lex has moved over some to the left closer to the edge of the window pane. (00:06:30)
Continuity mistake: After Tess walks in, Lex turns and begins pressing buttons on a small hand held device. There are three green lights at the top. When the angle changes, suddenly the lights are smaller and his grip on the device changes. (00:06:45)
Continuity mistake: At the Fortress of Solitude, Superman is shown trying to cure cancer. The large computer he is using has three screens in a semicircle around it. Throughout the whole scene there with him, the robot, and Lois, the screens keep changing positions or vanishing all together. (00:07:30)
Continuity mistake: The robot at the Fortress of Solitude has black arms, including most of the shoulders except where the pivot joint is visible. But for one shot when Superman is saying he wants to be more than Earth's resident strong man, the robot's shoulder is solid silver color like its torso. (00:07:55)
Continuity mistake: Superman's robot comes up to him shortly after Superman has a failure at curing cancer. The screen on his large computer shows the cells turn red and the word FAILURE appear. While Superman is saying he wants to do more than be Earth's resident strongman, it cuts to a close up of him. The cell arrangement on the screen changes, most noticeably on the right hand edge. These cancer cells change several more times during the scene. (00:07:55)
Continuity mistake: After Superman fails his experiment to cure cancer, Lois walks up wearing just a towel and holding a smaller towel, drying off from a warm bath. It cuts to a different angle and suddenly the parts of her hair draped over the front of her shoulders down her chest are shorter, and the ends of the hair go from a single point to being forked. Her grip on the smaller towel also changes, her hands closer together, and her mouth is suddenly open when the shot changes. (00:08:10)
Continuity mistake: At the Fortress of Solitude as Superman and Lois joke about him using X-Ray vision on her, Lois has her hand on his chest. When it cuts to a close up for them to kiss, her hand slightly changes position on his chest. (00:08:35)
Continuity mistake: Once the team at Project Applecore puncture Doomsday's spaceship, the hand held camera guy gets footage of it. When he zooms in, the location of the puncture hole changes closer to the edge and further from the yellow line than it was. It moves again when the alien hologram turns on. And then yet again after the hologram turns off just before Doomsday breaks out. (00:09:30)
Continuity mistake: While trying to clear away the rocks and dirt from around Doomsday's ship, they accidentally puncture it with the laser drill. But when Doomsday is about to break out of the ship, the hole they made has vanished. (00:10:05)
Continuity mistake: After throwing the guy out of the driver's compartment of the laser drill, Doomsday jumps down and smashes a guy into the ground, leaving a hole. During this same shot, Doomsday picks up the laser drill rig and crushes another guy with it, and suddenly the hole has vanished. (00:10:30)
Continuity mistake: When Doomsday breaks out of his ship and starts killing the people at Project Applecore, the area around the spikes on his body are the same color as his skin, just slightly lighter gray. But after throwing the laser drill rig at a worker, he jumps at and punches two more guys. The hand held camera one guy is using fades out for a moment, then back in. Now suddenly the area around Doomsday's spikes have turned blue. (00:10:45)
Continuity mistake: As Lex is deducing that the alien race that trapped Doomsday on Earth did so because they couldn't kill it, he walks towards his window and looks at his reflection. It cuts to a close up and suddenly he is much closer to the window. (00:11:10)
Continuity mistake: Once Doomsday makes it to the surface, he spots a deer and it is shown from over his shoulder. It cuts to a view of the deer from Doomsday's eyes and suddenly the deer has moved over some, and the rocks and grass around it have changed. (00:11:30)
Continuity mistake: After he hears Doomsday kill his dog, Biscuit, the guy with the shotgun runs outside to see what happened. The shot of him coming out the door shows a bush next to the steps of his front porch. But when it cuts to a wider angle, the bush has moved to the end of his house. (00:12:45)
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: As Lois is walking up to Superman from behind while they're both in red robes, she says "Look, I know who you are. Why can't you just tell me?" Superman's head is straight in that angle. But it cuts to a closer shot and his head is suddenly tilted to the side a little. (00:13:35)
Continuity mistake: When Doomsday looks up and sees a gas tanker driving by, it only has two lights on top of it. When it cuts to a close up, it has 4 lights on top. Also in the distance shot, the window and side view mirror on the passenger side are missing, but appear in the close up. (00:14:35)
Continuity mistake: As Doomsday is ripping the roof of the cab of the gas tanker, his mouth is open. It cuts to a close up of his face and it's suddenly closed. (00:14:50)
Continuity mistake: The driver of the gas tanker kicks around frantically as Doomsday is ripping him out of the truck and kills him. His foot goes through the driver's side of the windshield, shattering it. But the passenger side is unharmed because it is a separate window in this model of truck. The truck plows through the guard rail after Doomsday kills the driver and plummets to the ground, the passenger side of the windshield still fine. But in the shot of it just before it hits the ground, it is suddenly cracked as well. (00:14:55)
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