Continuity mistake: At the end, the number on the helicopter is 711. As it takes off it is 712. (01:26:30)
Continuity mistake: When the villain has the gun to Billy's head, in one shot it's touching his head, in the next he is about 1-2 feet away. (00:33:45)
Continuity mistake: At the beginning of the movie, Dolph Lundgren throws down the battering ram which has "Knock Knock" written on it. Shortly after one of their vehicles reaches the top of the ramp and one of the enemy jeeps falls off the roof Jet Li screams "Shut up, Gunner!" at Dolph Lundgren. Just before he screams, the "Knock Knock" battering ram is back in the retracted position. A few seconds later, it is facing the front again. (00:03:50)
Continuity mistake: When the bloke has the knife to Christmas's neck, the position of the blade changes instantly. Note the end of the blade and his ear. (00:35:50)
Answer: "We keep it light" refers to their mood. They joke around and tease each other and have fun. "Till we go dark" is when they get serious for killing. "We go pitch black." Meaning as dark and brutal killing machines as possible.