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