Here is the full list of all 29 Primal Fears achievements.
Find all newspapers
Pickup 100 moneypacks
Finish all missions in easy
Finish the map Laboratory
Finish the map Laboratory - Secret Entrance
Find 12 different newspapers
Finish the map Police Station
Kill 1000 creatures
Finish the map Suburb
Find five different newspapers
Bonus multiplier reached 200
Finish the map Mall
Finish the map Sewer
Find one newspaper
Kill 10 creatures
Kill 100 creatures
Finish the map Hospital
Finish a mission within time limit
Bonus multiplier reached 100
Bonus multiplier reached 50
Bonus multiplier reached 10
Kill 5000 creatures
Kill 10000 creatures
Kill 15000 creatures
Finish all missions in normal
Finish all missions in hard
Finish all missions in insane
Finish a mission in difficulty hard without being killed
Purchase all weapons in the campaign