Revealing mistake: All the zombies have greenish-gray, decayed skin. But when the zombie in winter camouflage gear is climbing the tree after Anna, his sleeve pulls back, revealing the actor's normal skin underneath. (01:00:40)
Revealing mistake: After Martin cuts his arm off, there are several scenes where you can see the bulge of the actor's real arm under his jacket. This is most noticeable when he is running through the birch wood, and when rooting through the ruins of the burned cabin.
Revealing mistake: The zombies' uniforms are all worn, decayed and dirty from being 60 years old, and being underground for most of that time. But there are some notable exceptions. The winter camouflage gear worn by two of the zombies is completely undamaged and pristinely white, and looks brand-new. In addition, when Vegard is thrown out of the zombie cave, the zombie who climbs out after him is wearing shiny black boots, that does not bear the slightest sign of having ever been worn.
Revealing mistake: When Anna is being chased by a zombie out on an ice shelf, we get a close-up of the zombie in his winter camouflage gear. You can see a modern pull-cord holding his hood in place.