Revealing mistake: When the body of Achilles lies on the pyre in the close-up, although the fake body has a similar appearance to the real Achilles, some things are different, such as the body does not have the distinctive circular scar on the left upper arm as Achilles did. (02:31:40)
Revealing mistake: Just as Achilles is hit with the fourth arrow in the close-up, on the left side of the screen, beside the statue, something suddenly appears in the shot and then disappears. (02:28:40)
Revealing mistake: When Achilles slices Hector's spear the two wood ends are jagged and the broken spear end that Hector later carries shows a jagged end on the wood. However when Achilles stabs Hector, as the spear protrudes from Hector's shoulder the wood end is perfectly even. (01:59:15 - 02:01:30)
Revealing mistake: Most of the Greek and Trojan armor, in their own respective ways, look more manufactured so they are perfect clones of one another. Real armor from that time would have had lots of imperfections and signs of being individually created and hand-crafted. (01:17:20)
Revealing mistake: At the start of the shot facing Patroclus (dressed as Achilles), as Hector's blade is up against his throat, then slices it, the ridged bottom of the fake latex throat that Garrett Hedlund (Patroclus) wears is visible, when he arches his head back. (01:43:25)
Revealing mistake: After the Greeks break through the palace gates, Paris releases the first arrow into a soldier. As he begins to turn around, the bent dark arrow unbends at his neck at the start of the shot, before it becomes the straight lighter arrow. (02:25:30)
Revealing mistake: Hector's sword is secured to the underside, from hilt to point, entirely under the shield, perpendicular to the handle he always holds. While Achilles and Hector duel, Hector snaps Achilles' spear with his leg. At the start of the next shot, Hector holds the grip of his sword and pulls it from the shield, above and parallel to the handle, not from where it should have been, obviously deliberately done to ready the sword for the shot. (01:59:25)
Revealing mistake: Throughout the movie, especially in the scenes which take place in the Troy encampment, no matter how many times Achilles gets dirty in battle and then cleans up, there is always a small smudge on his left upper arm. In the right light, you can make out the distinctive, small, circular scar of a small pox vaccination right where that dirt smudge is - it's really quite distracting. Until 1972 in the US this was a common vaccination given to children. (00:37:30)
Revealing mistake: After they arrive on Troy’s shore, a particular Myrmidon is hit and falls overboard into the water. After a few shots another Myrmidon is hit with two arrows and he too promptly falls overboard into the water, and then loses his wig in the water (after the helmet). (00:39:55)
Revealing mistake: Many of the spear tips and swords bend like rubber, some at almost a 90° angle and are fine in the following shots! Such as when Achilles' spear tip bends as it makes contact with Hector's shield, once when Achilles does his leap into the air at the start of the duel and then just after slicing Hector's spear with his shield. (Although weapons were made of bronze in those days, and were likely to bend, the fact that the weapons in the film bend to such a degree and then right themselves is impossible.) (01:59:10)
Revealing mistake: After Achilles and the Myrmidons arrive on shore, the Trojans let loose a barrage of fiery arrows, and when one lands in the thigh of a man still aboard the ship, the fake leg skin around the protruding arrow is quite obvious. (00:39:45)
Revealing mistake: The characteristics of the severe scars on Ajax's forehead, cheek and shoulders differ significantly in his close-ups. (00:41:35)
Revealing mistake: As Hector holds his son, the first warning gong is rung. In the next shot, when Hector hands the baby to Andromache, its small shiny bald head is quite a giveaway that it's really a doll in this shot (not visible on widescreen DVD). Later, Andromache holds her son, Scamandrius, when she finds Helen and Paris, as Troy burns. Aside from the fact that the door hits the back of the baby's head, he now has a bald shiny head, whereas he had hair in previous shots, so it's quite obvious in this shot that the baby is a doll once again. (02:23:05)
Revealing mistake: When Briseis sticks the knife in Agamemnon's neck, you can plainly see silver fillings in his teeth when his head is back. (02:27:40)
Revealing mistake: When Achilles is dying and saying farewell to Briseis, when the camera is facing Achilles, you can see the netting on Briseis's wig underneath her "hair". (02:29:25)
Revealing mistake: Paris' arrows have identical black plastic nocks at the end of each shaftment. (02:25:10)
Revealing mistake: When Agamemnon and the Greeks charge at the Trojans after Menelaus is killed, in the close-ups during the melee, quite a few of the spears actually wobble in the soldiers' hands, like for example, when the Apollonians throw their spears. (01:18:20)
Revealing mistake: When Menelaus slices Paris' leg the wound stops bleeding immediately after that shot. (01:15:15)
Revealing mistake: When Hector and Achilles stand outside the gates of Troy, they each remove their helmets. As Hector lifts his from the bottom it actually bends, like rubber, in his left hand, though the entire helmet is one solid piece of metal - there is no other material attached. (01:58:05)
Revealing mistake: The dawn after the Trojans have retaliated against the Greeks with their fiery assault on the beach, a light filter was used to make a midday shoot appear as though the sun had not fully risen yet. This is evidenced by two things. First, the shadows are not as "deep" as they would be at that time of day. All the details that shouldn't be visible at dawn are perfectly defined, it's just not bright. Second, the fires that still burn should be radiating a bright orange glow. Instead, they are just as dimmed as the rest of the light.
Answer: He doesn't yell any words, just an expression of anguish over his brothers death.