Revealing mistake: At the cave near the end, there are several scenes with the secretary of the interior. These scenes with the main actors appear to be filmed in front of the background as they cast shadows on the other film and the lighting is different. This was most likely done because of budget limitations.
Revealing mistake: When Ramón and his men massacre a detachment of Mexican soldiers by ambushing them with a Gatling gun, it's easy to tell that the soldiers are just pretending to be hit by bullets. There isn't a single bullet hole or drop of blood on any of the soldiers also in the wide shots not one horse is hit in the crossfire nor has the carriage been damaged by gunfire. (00:25:43)