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