Emplaced defensive guns Carl helps install in camp during the lull before the main assault.
In the gap between the destroyed cyborg beachhead and the arrival of the main force, the defenders reset their positions and loot the enemy dead. Carl is helping set up another anti-air gun when Samantha floats into camp coated in leaves and dirt.
The emplacements matter because the enemy is coming in force with armor and numbers, and the crawlers' own air power — including Louis's airplane — has shown that the sky above the castle is contested ground.
Emplaced heavy weapons being bolted into position around the camp perimeter.
Air-defense emplacements added to the castle's fortifications between assaults.
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