Here is the full list of all 49 How to Survive 2 achievements.
Give an ally an item for the first time.
Kill an infected with a charged attack for the first time.
Enter Kovac's bunker for the first time.
Finish your first co-operative quest (local or online).
Finish Kovac's first challenge while keeping the pylon intact.
Successfully complete half of Kovac's challenges while keeping the pylon intact.
Successfully complete all of Kovac's challenges while keeping the pylon intact.
Reach the maximum level with your character.
Kill 1,000 infected humans.
Kill 10 infected animals of each species.
Kill 50 nocturnal infected.
Successfully complete all of the elite quests.
Kill 5,000 enemies (of all types).
Kill 500 infected with a critical shot.
Kill 100 infected with silver bullets.
Kill 100 infected with flint-tipped fletched ammunition.
Kill 2 or more enemies at the same time with a melee weapon.
Kill at least 2 infected with one arrow or crossbow bolt.
Kill 100 infected with traps.
Kill 50 infected during a last stand.
Kill 10 infected with a Bomber explosion.
Have all "Survival" skills at the maximum level.
Have all "Weapon" skills at the maximum level.
Have all "Stamina" skills at the maximum level.
Have all "Special abilities" skills at the maximum level.
Have all "In Danger" skills at maximum level.
Have the camp at maximum level.
Cook every type of recipe.
Prepare every type of potion.
Make every type of armor.
Make every type of weapon.
Finish 15 co-operative quests (local or online).
Finish Kovac's first challenge in co-operative mode (local or online).
Customize your survivor for the first time.
Help an ally in trouble 30 times.
Pick at least one of every type of plant.
Upgrade a weapon with modules for the first time.
Upgrade 10 weapons with modules.
Finish each of the game's festive quests.
Prepare a first potion.
Finish every quest.
Drink 50 potions.
Hit a car under alarm with a trash can.
Equip a pet for the first time.
Pick a lock for the first time.
Pick 20 locks.
Join a public camp for the first time.
Meet every character in the game.
Wear the Jester's hat for the first time.