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