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