Here is the full list of all 50 Tomb Raider achievements. It takes around 40-50 hours to unlock all of the achievements on Windows.
Purchase all skills in all categories.
Complete the game.
Find all documents, relics and GPS caches.
Shoot a bundle of dynamite out of the air.
Fully mod and completely upgrade all weapons.
Complete all challenges.
Complete all optional tombs.
Complete all conversations with the Endurance crew.
Find 75% of all documents.
Fully mod and completely upgrade any weapon.
Rope pull 5 enemies off edges.
Collect 75% of all relics.
Find 75% of GPS caches.
Kill FeeFee the crab.
Kill and loot 10 flying animals (crows and gulls).
Kill 40 enemies with the shotgun.
Shoot 10 enemies off zip lines.
Kill 25 unaware enemies.
Kill 75 enemies with the rifle.
Purchase all skills in one category.
Loot 200 enemies.
In multiplayer, be the only player on your team that isn't dead or downed.
Collect 5000 pieces of salvage.
Perform 15 finishers.
Perform 50 headshot kills in the single player campaign.
Kill 35 enemies with the pistol.
Kill 50 enemies with the bow.
Kill and loot 10 small animals (rabbits, chickens, rats).
Find 25% of GPS caches.
Collect 25% of all relics.
Find 25% of all documents.
Complete one optional tomb.
Complete one challenge.
Kill and loot 10 large animals (deer, boar, wolves).
Force an enemy to drop dynamite that kills two people when exploding.
Incapacitate 25 enemies with dodge counter.
Complete a match in all multiplayer modes.
Kill 20 enemy players in multiplayer using a turret.
Kill a zip-lining enemy player in multiplayer.
Catch a player in a snare trap in multiplayer.
Survive 10 explosions in multiplayer.
Revive a teammate in a multiplayer match.
Win a ranked match in every multiplayer mode.
Kill 10 multiplayer enemies using your melee attack.
Kill 2 multiplayer enemies with a single explosive.
In multiplayer, escape death 3 times by using the rope ascender.
Purchase a new multiplayer character.
Reach level 10 in multiplayer.
Buy every upgrade and character in multiplayer.
Reach level 60 in multiplayer.