Early in the film, Jack ignores a Stavros decoy because "Stavros is a lefty". Yet Stavros smokes with his right hand, and fires guns and throws grenades with both hands.
The knife between the thug's toes changes positions between shots.
Jack is completely wet when he hooks himself outside of plane. In next shot, he is completely dry.
There is no cross marker next to the mine when Yaz accidentally steps on it. A second later there is a cross marker next to it and his foot.
In the opening scene, there is a railroad crossing sign to the right of Jack's vehicle after he smashes through the train car. In the wide shot, this sign is suddenly gone.
It's impossible to cut something in water with a laser.
A grenade thrown into a swimming pool will not produce a 30-foot flame when it explodes.
At the beginning of the movie a operative states that non-nuclear plutonium was stolen from a US Secured Nuclear Facility in Croatia. The United States does not have any Nuclear Facilities in Croatia.
Rodman's character is pushed out of the airplane by Van Damme's character, who then takes a couple seconds to jump himself. When he jumps, the shot shows that Rodman is directly below him, when the forward momentum of the plane would of placed Van Damme further ahead of Rodman.
Van Damme is training to hold his breath, for the duration it would take a cigarette to burn up. This would take over 5 minutes and would cause death or brain damage to normal people.
Stavros steps on the mine with his right foot, but steps off with his left.
When Quinn places the skin from his thumb on the eraser while planning his escape, blood is already on the eraser, probably from a previous take.
During the operation to assassinate Stavros at the amusement park, the moment Stavros is presenting a toy gift to his son, the sniper is asking via radio for Quinn's order to shoot. When Stavros fires at the sniper, she's right beside Quinn.
Toward the end of Jack's fight against Stavros in the arena, when Jack starts using more acrobatic and double kicks, Stavros' opponent is clearly Jean-Claude Van Damme's stunt double.
In the gun shop after the grenade explodes, Yaz says, "But no checks. And my rule is, you break it, you bought it," without moving his lips.
When Jack Quinn is backing away from tiger on the bridge, Jean-Claude Van Damme's stunt double's face is visible.
When Jack is attacked underwater during his escape from the Colony, his assailant tries to kill him by putting a bag over his head. Jack is already underwater, so trying to kill him via suffocation makes no sense.
In his e-mail message, Jack types "Stavro's".
Jack asks "Who his Dead-Eye?", slides a case with a precision rifle to the woman, and asks if she can shoot a target at 200 yards with it. She starts assembling the rifle and says "with this I can shoot the dick off a hummingbird". Like most birds, hummingbirds don't have a penis, they have a cloaca.