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.
Kill 20 enemy players in multiplayer using a turret.
Complete a match in all multiplayer modes.
Win a ranked match in every multiplayer mode.
Purchase a new multiplayer character.
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.
In multiplayer, escape death 3 times by using the rope ascender.
Kill a zip-lining enemy player in multiplayer.
Kill 2 multiplayer enemies with a single explosive.
Kill 10 multiplayer enemies using your melee attack.
Complete all challenges.
Find all documents, relics and GPS caches.
Find 75% of GPS caches.
Fully mod and completely upgrade all weapons.
Complete all optional tombs.
Purchase all skills in all categories.
Collect 75% of all relics.
Kill and loot 10 flying animals (crows and gulls).
Complete the game.
Shoot a bundle of dynamite out of the air.
Find 75% of all documents.
Incapacitate 25 enemies with dodge counter.
Complete all conversations with the Endurance crew.
Fully mod and completely upgrade any weapon.
Kill FeeFee the crab.
Kill and loot 10 large animals (deer, boar, wolves).
Purchase all skills in one category.
Kill 40 enemies with the shotgun.
Rope pull 5 enemies off edges.
Loot 200 enemies.
Find 25% of GPS caches.
Kill 25 unaware enemies.
Kill 75 enemies with the rifle.
Shoot 10 enemies off zip lines.
Collect 5000 pieces of salvage.
Force an enemy to drop dynamite that kills two people when exploding.
Perform 15 finishers.
Collect 25% of all relics.
Perform 50 headshot kills in the single player campaign.
Kill 35 enemies with the pistol.
Kill 50 enemies with the bow.
Kill and loot 10 small animals (rabbits, chickens, rats).
Find 25% of all documents.
Complete one challenge.
Complete one optional tomb.