Continuity: During the final fight sequence, Donnie's shoes change from boots to sneakers in several shots.
Plot holes: Simon and his gang of members were on their way to the crime scene when a police undercover was murdered and crossed path with a geek that had apparently videotaped the murder. He was not detained at all despite holding a video-cam in his hand and the guys just let him walked away. The next thing you know that same geek turned up at the police station.
Revealing mistakes: When Jacky Wu fights Simon Yam in the end Jacky throws a knife in Yam's hand. No blood appears and the hand bends like a rubber hand.
Continuity: During the final fight, Wong Po's phone changes model. When he is talking to his wife, Donnie kicks and he falls. The phone drops to the floor. In the next shot it appears again, it's a different model.
Continuity: In the final fight Donnie Yen kicks Sammo Hung on to the bar. Sammo bounces off it, seemingly falling to the floor. But in the next shot, Sammo is standing up against the bar. The shot after it he is even lying on it, when Donnie does an acrobatic move to crush him into the glass holder.