TedStixon

Revealing mistake: Throughout the final fight between Pyramid Head and the Missionary, you can tell that Pyramid Head's mask and sword are very light-weight and made of rubber or another soft-material. Ex. When Pyramid Head hits Missionary out of the arena with the hilt of his sword, in the wideshot, if you look through the flames, you can actually see the sword bobbing about in the air before the tip hits the ground as the actor can't keep it steady.

TedStixon

Revealing mistake: During the final fight, when the Missionary is "sawing" through Pyramid Head's metal helmet, if you look closely, the helmet has been pre-scored and that the actress playing the Missionary is just running the blade along the pre-cut line in a "sawing" motion. The "metal" of the helmet also blatantly bends like rubber during the moment, revealing it's not really metal.

TedStixon