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