Revealing mistake: Before the big battle between Lucius and Acacius begins, the soldiers arrive at the bleachers, where we see several shots of the people. Check the crowd, and you'll notice it's a flipped shot of the previous people. (01:33:32)
Revealing mistake: During the riot at the bleachers, a soldier grabs an arrow from the quiver, places it on the bow, tightens the string, and aims to shoot. The problem is, he's mimicking all the movements. He didn't pick up an arrow in the first place. Seemingly, someone forgot to place the CGI arrow. (02:09:02)
Revealing mistake: During the naval battle, after an underwater shot of a man being eaten by a shark, check the poop deck on the left, and you'll notice a bulky floor with wrinkles around where people fighting and falling bounce on, revealing a tarp hiding a safety mat.
