Here is the full list of all 29 Second Extinction achievements.
Respawn 20 times.
Kill 6666 Enemies.
Unlock all perks for one weapon.
Complete 40 Contracts.
Deploy 20 times.
Complete the mission ”Black Site".
Complete all core missions.
Complete 20 Contracts.
Deploy 10 times.
Complete the mission "Charged Extraction".
Complete 10 Contracts.
Complete the mission "Contact".
Complete a mission without any on the team having to respawn.
Kill 2000 Enemies.
Complete the mission "Homebound".
Kill 20 Enemies with Supply Drops.
Complete the mission "Vestige".
Kill 750 Enemies.
Complete the mission ”Research And Rescue".
Take a raptor with you when you extract.
First Deployment.
Respawn 40 times.
Respawn 100 times.
Deploy 50 times.
Deploy 100 times.
Play 20 missions at night.
Kill a T-Rex with a Supply Drop.
Complete a mission without using a Health Stim.
Find the golden egg.