Other mistake: Jack is rescued by Bridget at the train station where he is being pursued by Sandra (an alien). Bridget shows up in her car and drives him away so Sandra cannot catch him. But Sandra and Bridget have never met. How could she know Sandra was a threat? Even more confounding, how did Bridget know to find Jack at the train station? He was randomly thereafter jumping out of the car he was being abducted in. (00:50:30)
Other mistake: The number plate on the car that Bruce Willis is driving with Simon in has different numbers on the back from the front.
Other mistake: Right before Blade confronts Frost at the end, he is shown beating up several henchmen vampires using punches and kicks, before grabbing his sword. As he grabs his sword, you see several of the henchmen vampires "burning up" in the background. However, it was earlier established that to "burn up", vampires had to be killed by traditional means. (Staked with silver, exposed to sunlight, etc.) So it makes no sense for these henchmen to burn up from only being punched/kicked. It can't be due to his sword, as he twirls it in front of them, and only after they are already burning up.
Other mistake: When Riggs and Murtaugh are assigned as new captains, they throw their old badges to the Chief and he catches them in his left hand as he grabs the new badges out of the desk draw with his right. In the next shot where he passes them the new badges, he is not shown to have swapped the badges over, so essentially he passed the old ones back to them.
Other mistake: When Cain's eye is damaged in the fight the officer says he will only be good for cannon fodder, with no depth perception. So how can he be driving an armoured vehicle?
Suggested correction: He has been given a replacement eye, which takes care of the problem. He's just angry because Caine 607 didn't win perfectly and showed weakness by being out thought.
Other mistake: When Bruce Wayne is searching the database after the nurse leaves Dick's room, the screen initially has the vital stats (height, age etc) of Nora, Mr. Freeze's wife. (00:32:00)
Other mistake: When the company makes its first advance up the grassy hill through mortar explosions and flying bodies, as the guy next to Captain Staros takes a turn with the binoculars, watch carefully. You'll see he has them pointed down into the grass, not up the hill where the fighting is occurring. Further, the field has zero visibility from gunsmoke, which would prevent him from seeing anything anyway, even if he did have them properly aimed. (00:47:35)