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