Blooper

When Thel is shot, her head changes position in William Blake's arms between shots.

After William Blake and Nobody walk down to the trading post tent, William takes off his hat and is holding it in his right hand. When the camera angle changes, he is holding it in his left hand.

When William and Nobody are riding horses, William's jacket is hanging off his shoulders, in the next shot, his arms are in the sleeves, and a few shots later, his jacket is once again on his shoulders.

Blake buys a half-empty bottle in the bar. Minutes later, when he offers Thel a drink outside, the bottle is filled almost to the neck.

William Blake and Nobody come upon a trading post tent. When Nobody walks down the hill towards the tent, smoke from the chimney is blowing towards him, but when the camera angle changes, it's blowing away from him.

In the opening titles, after the train ride, Billy Bob Thornton's last name is incorrectly spelled "Thorton".

When Blake first arrives at the town of Machine, there's a workshop or factory in the distance, with smoke coming out of the chimney. But the smoke does not disperse into the air, rather it's blocked inside a cut-out shape of a drawing of chimney smoke.

At the end Nobody tells Blake he prepared the canoe with cedar bows. But you can see the needles on the branches are from Spruce or Pine.

The dead marshal's eyelids can be seen moving, just before the scene where Cole Wilson squishes his head.

Conway Twill sleeps with a Teddy Bear in scenes set in the late 19th century. The Teddy Bear was invented in the early 20th century, and named after US President Teddy Roosevelt.

While the three bounty hunters are waiting in the office, Conway asks Johnny for tobacco, then dismissively says that Johnny isn't even old enough to smoke. There would have been no laws governing tobacco use by minors at the time this movie was set, and persons as young as nine or ten might have smoked or chewed tobacco without raising much comment other than that tobacco was considered a bad habit in the young. The thought that Johnny was too young to smoke should not have even crossed Conway's mind. (It is also possible that Conway was simply commenting on how extremely young Johnny is in general--that he's too young even to have picked up such a habit.)

As Blake follows Nobody through a canyon, both on horseback, a crewmember is briefly but clearly seen crouched and walking between the two horses.