
This is from season 5’s 10th episode. A device which looks like a laptop charger can be clearly seen under Stannis’ leg. People on Reddit theorized that it was a device which is used to pump fake blood out.
2. Looks Like That Guy Went To Heaven In His Physical Body In Season 5’s 4th Episode.

Such mistakes, much wow.
3. This Is Also One Of The Most Noticeable Plot Mistakes Made By Game Of Thrones.
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The true form of Lady Melisandre could be seen when she took off her magical choker in season 6 right? Then how come she’s seen without one in season 4 without any repercussions?
4. Get A Grip Game Of Thrones!

In season 1’s 9th episode, Jon keeps switching his grip on his sword. His grip on the handle is constantly changing between shots.
5. The Pointy Mistake Season 1 Episode 8.

Just after Jon is told he is confined to quarters, there is a shot of outside with the snow rising up instead of falling down. Which means the shot was probably reversed.
6. The Mistakes Continues…

In the same episode, Catelyn Stark’s hand mysteriously disappears between shots. Now that’s a careless mistake Game of Thrones!
7. You’ve GOT To Listen To This!

Listen to what you ask? That email chime which slipped into the shot which was one of the many mistakes Game of Thrones made in season 3. It’s quite faint but it’s there.
8. The Curious Case Of The Bloody Sword.

Robb Stark’s blades are already bloodied before he starts fighting off the bandits in the woods, the blade was clean when he unsheathed it.
9. That Wasn’t The Last Of The Bloody Sword.

Blood magically reappears after being wiped off. Magic?
10. His Sword Is Stuck!

He’s probably dead in the Game of Thrones universe now.
11. The Dirty Clean Horse.

Brienne’s horse is dirty in one shot, clean in the next shot. Some more magic.
12. Season 1 Episode 6.

There are two skylights in the ceiling when Tyrion wakes up inside the sky cell but when we get a long shot of the skycells, you can see that the two skylights are impossible given the layout of the area. The floor above him doesn’t have any holes!