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