The Man Who Wouldn't Talk - S2-E3
Revealing mistake: Maria's Spanish accent keeps disappearing, giving way to the actress' natural American accent, throughout the episode. Her supposedly Spanish aunt's accent is never Spanish to begin with - it's identifiably Austrian. (00:08:00)
The Protege - S2-E6
Continuity mistake: When Sprague is practicing shooting for the second time, we see that Paladin has put up a new target with no holes in it. Sprague draws his revolver and fires three shots but the cut to the target shows 4 holes in the center. He then proceeds to fire the other 3 shots. (00:10:15)
Lady on the Stagecoach - S2-E18
Continuity mistake: About 1/3 into the show, Paladin is walking towards the stage house, there are two bullets sticking up in the back of his gun belt. Once inside, all the bullets are now pushed down in their proper positions in the belt.
The Return of Roy Carter - S2-E32
Revealing mistake: When Maggie the saloon girl starts gathering the money from the floor, an equipment shadow intrudes at the left of the screen. (00:04:30)