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