Continuity mistake: The Flash trips in a field with loads of cacti. One of them changes in appearance between shots. There is also a two foot tall cactus with no branches next to it that disappears. (00:43:10)
Continuity mistake: The Flash is back at Wayne Manor with Batman, after regaining his powers. In the wide shot of the Manor's interior, the windows are about 5 feet in height. The next shot shows the windows now only about two and a half feet in height. (00:45:05)
Continuity mistake: When The Flash is on Batman's computer, the number of windows cracked/smashed changes between shots. (00:45:10)
Continuity mistake: Overlooking the crater left behind by Superman's ship in Metropolis, Flash and Batman are standing on the roof of a building with concrete tiles. The tiles change in size a few times during this scene, most notably bigger when Cyborg looks up at a satellite. (00:46:10)
Continuity mistake: At the meteor crater in Metropolis, Flash and Batman are standing very close to the edge of the roof of a building. A few shots later, they are about twice as far from the edge. And then there is suddenly enough room for Cyborg to land between them and the edge, and Flash be able to take a few steps forward towards Cyborg. (00:46:15)
Continuity mistake: As Cyborg is opening the door to Superman's cell, several layers of blast doors open one at a time. The last one to open you see for a moment as it begins to slide, you can see the room beyond through it in red. It then cuts to the other side and suddenly there is yet another layer of door that is opening by just sliding to the right, preventing any possibility of a view seen less than a second before. (00:49:30)
Continuity mistake: When Flash, Batman, and Cyborg walk into the cell that is holding Superman, a shot of just Superman's legs show that they are down with his knees on the floor. It then cuts to an angle from the trio and suddenly his legs are bent up and his knees in the air. (00:49:35)
Continuity mistake: While walking through the sewers, Flash is holding up Superman and beside Cyborg. Cyborg tells Superman that there are heroes, and Superman looks up at him asking "Heroes?" The next shot is from a different angle, and Superman is suddenly looking down again. (00:50:35)
Continuity mistake: After rescuing Superman, Cyborg, Batman and Flash step out into the open and are quickly confronted by several heavily armed boats full of government people. There are boats in front of the four of them and none to the side. But when Cyborg steps forward saying he can resolve this peacefully, two boats suddenly appears to their left slightly behind them. Then when the shooting starts, those two boats vanish. (00:51:10)
Continuity mistake: After catching the rocket and saving Cyborg and Batman from it, Superman turns and drops the exploded rocket and begins lifting into the air. It cuts to a wide angle as Superman is hovering above the ground, and the rocket he just dropped is nowhere to be seen. (00:52:05)
Continuity mistake: Batman and Cyborg have their backs to the tunnel they just came from and are shooting at the boats in front of them. Some soldiers come out of the tunnel behind them and fire a rocket in their direction. Superman suddenly jumps in and catches the rocket and it explodes. The blast knocks Batman over the rock he was hiding behind so he is on the boats' side of it, not the tunnel's side. But moments later when he is getting up and twp solders are rushing him, he is suddenly back on the side he came from, just before Superman vaporizes the soldiers with his heat vision. (00:52:10)
Factual error: Superman begins shooting his super intense heat vision at the soldiers attacking him and the other heroes. His vision cuts boats in half, and incinerates the soldiers into ash in an instant. The lasers from his eyes are super strength, with him not yet knowing how to hold any of it back or shut it off, and it is going through the soldiers and boats. Yet the vision leaves no damage at all to the ground the soldiers were standing on, nor does it create any steam when going across the water cutting boats in half. (00:52:15)
Continuity mistake: On Batman's plane, Flash walks up to Batman's seat, places his left arm on the top of it, stretches out his right arm to the side and says "Bruce's Batplane was a little more... stoic." It cuts to a close up of Batman and suddenly Flash's right arm is crossed with his left arm and his hand on his arm. It is still like that when it cuts away again. (00:55:50)
Continuity mistake: During their fight, Aquaman gets off a good kick on Wonder Woman and sends her flying backwards. She hits the ground and starts sliding. She goes between two other Amazons before stopping. It cuts to a close up and suddenly the Amazon on her right that she slid past is suddenly where she has not slid past her yet. (00:59:45)
Continuity mistake: After Wonder Woman smashes Aquaman through a wall into a building, he elbow drops onto her and then smashes her face into the floor, leaving a hole. The it cuts to a wide angle and he picks her up to throw her. The hole left behind from her face is now gone. (00:59:55)
Continuity mistake: Just after Wonder Woman and Aquaman argue a brief moment about her killing his wife, they continue their fight. Between the close up and the far shot, the rubble by the wall they are next to changes significantly in shape and amount. (01:00:20)
Continuity mistake: After dodging a low attack, Wonder Woman jumps into the air and slashes down at Aquaman with her sword. Aquaman raises his trident and blocks the attack, but is only holding the trident with one hand. It cuts to a close up and instantly Aquaman is two handing the trident. (01:00:25)
Continuity mistake: While fighting in the building, Wonder Woman gets up from some rubble and throws Aquaman through a wall leaving a hole. She then chases after him and they talk for a moment before suddenly Flash comes in and starts pounding on Aquaman. Cyborg then blasts Wonder Woman backwards. She flies at the very same wall, but now there's no hole and she makes a new one going through it. You can tell that it is the same wall as when she and Aquaman went through it the first time, her back was to the wall. She never changed positions or location at all until Cyborg comes in, and he blasts her straight backwards. (01:00:35)
Continuity mistake: After crushing the skull of an Amazon, Black Manta who shoots concentrated heat vision turns his attention to Batman. There is a purple car beside him. A couple shots later before he blasts at Batman, the car has turned black, and moved a lot further away from him. (01:01:35)
Continuity mistake: Batman is blasted against a green car by the guy with heat vision. He runs to the next vehicle as the heat vision guy shoots a ray at the green car, and the next shot shows the car is now purple. (01:01:40)
Chosen answer: Despite the ending in Flashpoint to indicate a Darkseid invasion, War is not a sequel. It's a reboot. While both films were part of the DC Universe Animated Original Movies series, War is the first movie of the series that is now part of the DC Animated Movie Universe. This is also why the voice actors are different.
Bishop73