Corrected entry: When Draco is struck by Medusa's arrow, he falls onto the arrow's tip which is sticking out the left side of his back. However, when he breaks off the arrow's tail from the front, it is now going straight into his chest, rather than at the angle for it to have come out his left side that we previously had seen.
Corrected entry: Medusa is significantly injured by the Djinn before she confronts Perseus. After Perseus slays her she falls into the lava pit. Right before she falls it shows a full shot of her serpent body, which suddenly has no injuries.
Correction: Not true. As she is falling, a very noticeable gash can be seen in her tail.
Corrected entry: In the last beach scene you'll see Pegasus flying in. The real horse's footprints are on the beach on a spot where the flying version has not been.
Correction: Those aren't hoofprints, but rocks, wave ripples and divots on the beach. Pausing the Bluray, it's possible to see the marks are too random to be prints.
Corrected entry: In the last scene, where Io is resurrected, her chest is very uneven, and disproportionate to the rest of the movie.
Corrected entry: Following the exit from the battle with Medusa and watching the death of Io, Perseus picks up his sword and the wrap containing the head of Medusa. Then, in the next shot, the wrap has gone from his left hand and he is just carrying the sword in his right.
Corrected entry: When the people of Argos learn from Hades that Perseus is a demigod, the soldiers bring him downstairs to question him. He has the line, "I mend nets, not wield a sword." This is improper grammar and appears to be a mistake rather than for the purpose of building his character. He should have said, "I mend nets. I don't wield swords," or "I was meant to mend nets, not wield a sword." (00:22:25)
Correction: He's also a mostly uneducated fisherman. And perhaps the way he speaks would be proper in Argos. And many people in today's society would speak the same as he did.
Corrected entry: In the scene after Perseus is healed from his Scorpion bite, he stands up in front of a large rock wall. A very visible tear is above his head to the left, flapping in the wind. This reveals that this is a backdrop. It is in several shots.
Correction: That's not part of the rock wall, it's part of the shelter he was laying under.
Corrected entry: Io tells Perseus that no man had ever ridden a Pegasus before, implying that Perseus would be the first; however, Perseus is not a man but a demigod, and as such he cannot be the first "man" to ride a Pegasus.
Correction: Io tells Perseus what he needs to hear to get him moving; that doesn't have to be the absolute truth. Perseus, as it made pretty clear throughout, hates the fact that he's a demigod and is shown to reject to the point of irrationality anything related to the Gods. Telling him that he'd be the first demigod to ride a pegasus would be more likely to make him stalk off to find something else, probably while shouting that he "can do this as a MAN!" By equating him with mankind and leaving out any reference to his divine ancestry, Io is able to point him in the right direction without risking him taking offence.
Corrected entry: When Perseus and Calibos fight during their first encounter, Calibos bites Perseus in the arm hard enough to take a small chunk of his flesh out. This injury disappears in the next shot and is never present again.
Correction: The bite is a plot point and is seen several times until it is healed.
Correction: Medusa's arrow went through him, at an angle. It went in the right side of his chest. And out the left side of his back, where he rolled over to break off the tip. Then snapped off the back on the right side.