Audio problem: After the Trojans start to fire arrows at the ship, the second Myrmidon who falls overboard into the water, screams loudly as he falls, though his mouth is clenched shut. It is the type of yell that cannot be made with a closed mouth. (00:40:00)
Audio problem: When Hector is giving his speech to the Trojans as they stand outside the gates in face of the oncoming Greeks, he gives his final line of the speech and there is a rousing cheer from the soldiers. However, none of the soldiers move in any way in the wide shot. (00:38:35)
Audio problem: When the Myrmidons arrive on Troy's shore, as the Trojans let loose fiery arrows Eudorus shouts to the men, " Forward!", but his mouth clearly says something entirely different. (00:39:55)
Audio problem: When Agamemnon and the Greeks are retreating, Odysseus shouts, "Back to the ships!" in a close-up while he rides with Agamemnon on his chariot, but his mouth is not in sync with the words; nor is Agamemnon's when he shouts the same in the previous wideshot (not his close-up). (01:21:55)
Audio problem: While Troy burns, when the horse gallops down the corridor, as Briseis runs she shouts, "Paris!" and though her mouth continues to shout what looks like "Andromache!" no sound is heard. (02:23:20)
Audio problem: After Achilles says, "No Greek will attack Troy for twelve days," Priam sees Briseis and his lips move but nothing is heard, then when we hear him say, "Briseis?" his mouth does not move. (02:10:20)
Audio problem: Before the first battle between Trojans and Greeks, we see an overhead shot of the Greek warriors walking over the hill to Troy. We hear the sounds of their shouting, clanking armor, and the heavy rhythmic sounds of organised marching upon sand, but none of the warriors are walking in formation. (01:07:35)
Audio problem: As Troy is burning, Andromache finds Helen and Paris, and says, "We must go!" then Helen says, "Paris! Paris!" but their lips do not match those particular words. (02:23:05)
Audio problem: When the Greeks are sacking Troy towards the end of the film, you can hear a soldier yell "Aquí" twice. Aquí is Spanish for here. Most of the movie was filmed in Mexico and used Mexicans as extras.
Answer: They didn't know the Greeks weren't bringing cavalry. The Greeks did use them and sometimes brought them by sea. It was there to stop a cavalry charge and to break up fighting formations.
LorgSkyegon