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