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