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