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