Toombs's (Nick Chinlund's) line regarding Crematoria, "If I owned this place and Hell, I'd rent this place out and live in Hell", is paraphrased from an infamous quote General Phil Sheridan made during post-Civil War Reconstruction, in which he said, "If I owned Hell and Texas, I would rent out Texas and live in Hell."

The Purifier's line, "I've done unbelievable things in the name of a faith that was never my own", was not originally in the script. It was improvised by Linus Roache, and writer and director David Twohy kept it in the movie.

In her autobiography "And Furthermore", Dame Judi Dench says that she never really understood what was going on in the movie, but she enjoyed the experience of making the movie, and she thought the sets were great.

Vin Diesel wanted Dame Judi Dench to play Aereon, and went to great lengths to get her. A long-time fan of Dench, he had her dressing room filled with bouquets of flowers, and also advised her that they could not begin casting the movie until she agreed to accept the role.

The actors inside the Lensor costumes were skilled in body movement. Some were from Cirque Du Soleil.

Continuity

When the convicts are running through the clouds of falling ash, they get it all over their clothes and their hair, then an instant later, all the ashes are gone.

When Kyra removes the cup that Riddick used to kill a guard on Crematoria, the cup has a badly broken and jagged rim and its handle is attached about an inch below the rim. In the next shot where the cup is completely visible, the cup's rim is less broken and jagged and its handle is attached at least two inches below the rim. The cup she places on the rock appears the same as it did when she first picked it up.

After the Imam is killed, Riddick finds the Imam's tooth necklace on the ground. When we first see it there are small drops of blood around it. But only a few seconds later when Riddick goes to pick it up there is now a large half-moon shaped pool of blood next to it.

In the scene on Crematoria where Riddick is going to kill the guy with his "Tea" cup, he is obviously drinking something out of the cup. The final sip does not show him consuming the entire contents, but when he turns it upside down, not even a drop is left.

When Imam is checking if the way is clear for his wife and daughter, directly after the initial Necromonger landing, the debris on the ground around him moves from one shot to the next.



Factual errors

A surface with a 700F surface would not have shade cool enough to safely stand in. Even the underground prison would be uninhabitable. Also parts of the ground would be molten.

Despite Crematoria having both a dense enough atmosphere to support human life AND 700 degree temperatures, there are no hurricane force winds that would exist in such an environment, especially when the temperature was transitioning from hot to cold. The expectation that something should happen but does not does not constitute a Goof.A planet that has a literal 1000 degree (-300-700) difference would have to be extremely close to its sun, and have a barely existent atmosphere (Our planet Mercury has these same characteristics). Therefore breathing would be very difficult, if not impossible especially for running and climbing great distances.

While waiting to go to the hanger, the Riddick & the others are on a hill. The "seekers" can tell who is alive by body heat. However, the prisoners are shown to be on cooled lava with the still molten lava visible beneath them. One, they wouldn't be able to be so close to what was still molten but this would make THEIR body heat undetectable to the seekers.

When Riddick is lowered into the prison on Crematoria, he breaks his chains by spinning up the rope and then back down violently. It would actually create a greater force and be easier to get up the rope if Riddick just climbed straight up the rope then dropped straight down, creating far less resistance than spinning down the rope.



Incorrectly regarded as goofs

After Riddick is left on Crematoria by the Necromongers he takes shelter in a garage. Because the planet is quite obviously devoid of any humidity at all, the thin atmosphere does not transmit heat. Therefore, all shade on the planet; including the "night side" (the half of the planet that is in its own shadow) is much cooler. A similar effect can be seen in desert areas of Earth. Ironically, the extremes mentioned mean that the garage actually would require heating of its own to keep the occupants alive.

After Riddick kills the first inmate with his tea cup and threatens the second with his can opener, the remaining two haul a comrade out but it's not the guy who was killed. It's actually the guy wounded by Kyra earlier in the scene.



Revealing mistakes

When Riddick climes the rope on Crematoria, Toombs is hanging on the same rope, but when Riddick reaches the top, it's obvious that there's no weight on the rope below Riddick.

When Riddick is crouched on a perch looking up at the Necromongers entering the atmosphere of Helion Prime, the digital addition of the 'shine' of his eyes doesn't match up with his eye and head movement.



Anachronisms

The can opener key used by Riddick to scare off the bully boys is way out of its time period.



Audio/visual unsynchronized

At 41:35 when Dame Vaako is speaking to her husband and applying her eye "make-up" the close-up shot reveals that her cheeks are not moving at all while the dialogue is being spoken. She would learn to keep her cheeks immobile after burning her eyeball often enough.

While Running through the Canyons of Crematoria the second time Kyra yells, "Riddick," her lips don't move.



Crew or equipment visible

The green screen used to create the mountains and deadly sunrise on Crematoria is reflected in Riddick's goggles.

When the Holy Man is cornered by the necromonger before attacking each other, the reflection of the lights on the set can be seen in his glasses.

When Imam is talking to Riddick about him leaving Jack, the reflection of the Camera lights is visible on his glasses.



Plot holes

Water boils at 212F so at 700F all the water in the canteens would have been vapor once Riddick opened them. It would not help him stay cool enough to go in the sun. Even then Kyra didn't get soaked in water, yet she didn't get burned. Just as the sun rises, the temperature hadn't yet got up to 700?. People can stand temperatures hot enough to cook a steak for an hour if there's no humidity.



Character error

Despite being exposed to 700 degree temperatures (even for seconds) Riddick is shown to be completely uninjured when he is dragged into the prison's hangar. He should have had at least second and third degree burns on his outer skin. This happened seconds after the sunrise, well before the temperature got up to 700? and he was out there under a minute before the Purifier dragged him in.

When confronting the leader of the Underverse with Kira at his side, when the leader offers "another way, the necromonger way" Riddick?s eyes are not blue/white anymore, but Vin Diesel style.