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