Vestige

Vestige is the fourth mission in the Tundra Campaign of Second Extinction. The objective of the mission is for the Extinction Unit to locate a deceased Scout Unit and acquire their audio logs, the team must then use a Scanner to locate a T-Rex nest and capture four eggs to be sent back to Gateway Cygnus for study.

Mission Brief
EX-U! As you are well aware - to defeat one's enemy, one must know one's enemy. Not long ago, a Unit was sent down to gather Dinosaur eggs for research. We unfortunately seem to have lost contact with them and... well, I need you to go in, find out what happened to our Unit, get them out if they are still alive, and lastly: complete their mission by acquiring those eggs! It would further our research greatly. Sarah will fill you in on the details. Good luck!

Find the missing Scout Unit
After dropping in to their chosen insertion point, Sarah will send the EX-U the last known coordinates of the missing Scout Unit, with the team's task being to locate them. Upon arriving at the location given in the coordinates, the EX-U will find the Scout Unit dead and dismembered.

Search for the logs
With this morbid discovery, Sarah informs the team that she'll alert the Director of the Scout Unit's fate and instructs the team to find the Scout Unit's audio logs, if they're still intact. The logs are found on the corpse of one of the Scout Unit's members and show that an ERA researcher had managed to tag a T-Rex with a tracker before being spotted by the Dinosaur and ultimately killed.

Use a Scanner to find the T-Rex nest
After hearing this, Sarah instructs the EX-U to call in a Scanner and use it to find the Rex nest by tracking the T-Rex that had been tagged. Using the Scanners to track the the T-Rex, the team traverses their way through Altum Valley until they reach the entrance to the cave that houses the nest.

Harvest eggs from the Rex Nest
Standing outside the nest, Sarah tells the team to point out where they want her to send down some Carriers for the eggs. The EX-U then make their way inside the nest and find the eggs, alongside their angry mother. The team must then extract the eggs using the Carriers, while avoiding the mama Rex, or they may try to kill her if they wish. After securing two of the eggs, a slew of Raptors, Diggers, and Electric Raptors begin to attack. Once all four eggs are secured, the Carriers are sent up to space and Sarah commends the team on their work and the value of the eggs they recovered.

Reach an Extraction Point and get out
With the eggs secured, the EX-U must get to an and hold out for Sarah to bring the Raft down to them so they can escape and head back to Gateway Cygnus. The nearest Extraction Point is in Altum Valley or Tineis Harbor, depending on which nest the T-Rex was at.

Mission Debrief
Today is a tragic day. The brave people who lost their lives in the name of science shall not be forgotten. However, thanks to their efforts, and yours, we may now have the resources and the knowledge to turn the tide of this war. Well done EX-U.

Trivia

 * Vestige is currently the shortest mission in the game.
 * Vestige is one of the two main missions of the Tundra Campaign that has a guaranteed T-Rex spawn, the other is Contact.