In the ice cream shop, Julia asks Lucas about his dad and little brother to which Lucas abruptly says he has to go, stands and leaves. As Lucas stands his ice cream is half finished, with the spoon sticking straight up out of the cup. Lucas then tells Julia not to follow him again and walks out of the frame where it can now be clearly seen that his ice cream cup is full, with the spoon is lying across the top.
At around 17 minutes Julia's coffee mug changes from being on the newspaper to being next to the newspaper.
When the Wendigo first emerges through Frank's mouth, the jaw is separated from the skull and the cheeks are split leaving the lower lip dangling with the jaw. Later in the cave when the window go has a full reveal the face is dangling from its skull but the lip is still attached leaving a complete mouth hole.
The flag on the uniform that Paul wears is facing the wrong way.Police uniforms have the flag with the stars facing the rear while military personnel have the flag with the stars facing forward.
The Wendigo is from mostly Algonquin mythology, which great plains and East coast. 1 to 2,000 miles from the setting of the movie in Oregon.
The announcer on the radio playing at the convenience store mentions something about Crispus Falls, Oregon but Crispus Falls is located in Washington State.
When Lucas shows Julia his drawings just before the attack in the shed, the picture he drew shows the Wendigo emerging from his father's mouth, but Lucas wasn't home to see that happen. He also wouldn't know that the monster is his father and would have assumed it killed his father. So he would not know to tell Julia that his brother is with his father/monster and that he will come back for him, either.