The distinctive feature of the Point Extraction mission is the extraction platform in the middle of the cave. It has 4 guard turrets, each equipped with an automatic cannon ammunition supply (400 rounds). The turrets will fire at any alien within their range.
Enemies in Point Extraction missions attack frequently, even outside the swarm. Therefore, it is important to defend against them properly and conserve ammunition - the available Nitra allows you to call a single supply drop.
If you are playing with a team, try to always take one Gunner on a Point Extraction mission. This class can handle the defense of the drilling rig, while the rest of the team can focus on collecting Aquarq crystals.