Visible crew/equipment: When the men are pushing the catapult to the gate look at the far left of the screen for a few seconds you can see a crew member in a baseball cap and then a large movie camera. There's also a twig palisade next to him where two more crew members are visible.
Continuity mistake: When Smee gives Hook his nightcap drink, Hook takes it in his hand and holds it at the top of the goblet so that it is hidden under his hand. But in the very next shot he is holding it by the handle and the whole goblet is now visible with a small black umbrella sticking out the top. Additionally, the position of the small umbrella that sits in the goblet changes a few times. (01:02:40)
Factual error: When Peevey gets stuck in the truck, Cliff fires up the rocket pack and simply pushes it clear. If the rocket pack can push out enough thrust to move a 2 1/2 ton truck, Cliff's body can't take that kind of stress. He stretches his arms out, starts pushing, and sets off the rocket, putting himself between the truck and an accelerating rocket demonstrably capable of moving it. The truck is stationary so has 2 1/2 tons of inertia. The rocket instantly accelerates it to an appreciable speed. Human arms cannot take that kind of stress. He's going to be crushed.
Continuity mistake: The king's youngest daughter climbs down a wall and drops a tightly sealed Erlenmeyer flask (invented centuries later) filled with a toxic potion. The flask is full when it is dropped, but partly empty after it has been caught and handed back to her by her spouse's earlier visitor. (01:08:40)
Continuity mistake: When Fausto hands a tape from the back seat of the car to put on, he pulls it out and it is white. In the next shot when Demi Moore takes it, it is black.
Continuity mistake: When the Turtles first arrive on screen behind Keno, they leap over the boy to attack the thieves. Their order from left to right when they walk up is Mikey, Leo, Donny, then Raph. The very next shot shows them in the air, and the order is now Mikey, Donny, Leo, then Raph. Donny and Leo switched places between shots. (00:03:35)
Revealing mistake: Gratuitous car explosions are nothing new in action films ... but this time the ambulance explodes in mid-air before even hitting anything. (00:32:22)
Other mistake: Just before the evil robots capture Bill and Ted's girlfriends, after they crash through the window, the girlfriends ask the robots: "Who are you?" and Bill goes "Well, I'm really Evil Ted!" and unzips himself and out pops Evil Ted, and the other robot goes, "And I'm really Evil Bill!" and out pops Evil Bill. When the robots are herding the girlfriends out just before knocking them out with their breath, you can see two sets of clothes in the bottom left corner if you watch closely.
Continuity mistake: At the western bar Louise is drinking a margarita. As the shot goes back and forth between Thelma & Louise, the contents of the drink magically decrease and increase again. The level of Thelma's coke rises as well, when Harlan leaves them. (00:14:00)
Continuity mistake: At the end when Jack (Ethan Hawke) is nailing the roof of his cabin he stops and looks around with the nails in his mouth. His head turns and the camera goes back and forth and suddenly the nails are in his hand. He then runs down the latter with no sign of the nails anywhere.
Revealing mistake: During the night surfing scene notice that the sun is evident in the background (look closely it does not appear long). There are also shots where you can see clouds and faint blue sky. Moments later you see Keanu and Lori sitting in the water with completely different lighting which was actually taken at night and further distinguishes that the surfing shots were not actually done at night time. I heard the scene was shot during the day with a filter so it looked like it was shot at night.
Factual error: In one of the train cars on the way out west, upon being asked by one of his henchman, "When are we going to eat the mice?" Cat R. Wahl replies, "Which would you rather have, the crouton or the entire Caesar salad?" Caesar salad was not invented until the 1920's and the movie takes place in the late 1800's.
Continuity mistake: Chuckie falls into the river. When Bingo rescues him, his bike is in a different place in the river.
Character mistake: When the Tradewind arrives at the island, captain Hilliot says, "They might not be civilized," to which Richard replies, "Civilized: c-i-v-i-l-i-Z-I-D."