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