Revealing mistake: During the flashback when Sangha tells his goon what happened to Kurt Sloan after Tong Po battled him, a water machine is visible at the top of the screen spraying out a rain-like effect.
Revealing mistake: When David delivers the final kick to Sanga, he raises his left leg to kick but in the next frame it is his right leg which comes out and makes contact to Sanga's face. The right-leg is also a prop made of rubber as you can see the crews hand holding onto the thigh part and the rubber foot flopping/wobbling when contact is made. The following frame shows David bringing back his left leg after the right-legged kick.