Revealing mistake: In the funeral scene where Dr. Viper Lady is videoing Logan fighting, she starts lowering the smartphone, but the "faked" image on the screen doesn't change to match her arm dropping down.
Revealing mistake: When Logan slices his abdomen open to pull out the parasite around his heart, watch the (digital) wound at the bottom of the screen right before he says the line "You're not gonna wanna watch this part!" Not only does a small line of blood on the left of the wound simply "blink" into existence instantly at the bottom of the screen right after he pulls the claw out (slip up in rendering), but the wound itself doesn't quite 100% match up with Logan's movements - when he breathes in, the wound doesn't really move properly with his abdomen as it inflates.
Chosen answer: It was the first issue of the Wolverine comic, the 1982 limited series by Chris Claremont and Frank Miller.
Sierra1 ★