Revealing mistake: When making traps, he's harvesting powder from a spent shell (primer has been struck). (01:05:50)
Continuity mistake: RZA is first seen using a bolt action rifle in a left-handed configuration but in later shots the rifle is right-handed. Not sure if they mirrored the image in the close up because they couldn't get the right camera angle or if they were genuinely trying to make his character appear left-handed. (01:16:02 - 01:17:49)
Other mistake: While being shot at in the Challenger, you can see most of the rounds impact on the driver side door but more importantly the bulk land where they would be hitting Hutch without a doubt, and car doors aren't bulletproof. (01:15:01)
Revealing mistake: When you see Hutch walking backwards through a doorway firing his gun, you can see an actor in the background in the entrance looking directly at the camera. As Hutch passes past him, he puts his head against a wall and plays dead again. (01:18:32)
Continuity mistake: When the Russians drive up to the house, they are in a van and 2 sedans. They leave in the sedan that he crashes. When they leave, the van is gone. (00:48:14 - 00:50:47)
Answer: Van Gogh's "Bedroom in Arles".