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.
Fully mod and completely upgrade all weapons.
Complete all challenges.
Find all documents, relics and GPS caches.
Incapacitate 25 enemies with dodge counter.
Complete all optional tombs.
Purchase all skills in all categories.
Find 75% of GPS caches.
Collect 75% of all relics.
Find 75% of all documents.
Complete one challenge.
Rope pull 5 enemies off edges.
Find 25% of GPS caches.
Purchase all skills in one category.
Complete the game.
Fully mod and completely upgrade any weapon.
Collect 25% of all relics.
Loot 200 enemies.
Complete all conversations with the Endurance crew.
Collect 5000 pieces of salvage.
Kill and loot 10 flying animals (crows and gulls).
Find 25% of all documents.
Kill FeeFee the crab.
Shoot 10 enemies off zip lines.
Kill 40 enemies with the shotgun.
Kill 75 enemies with the rifle.
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 25 unaware enemies.
Buy every upgrade and character in multiplayer.
Reach level 60 in multiplayer.
Kill 50 enemies with the bow.
Kill 35 enemies with the pistol.
Perform 50 headshot kills in the single player campaign.
Win a ranked match in every multiplayer mode.
Kill and loot 10 small animals (rabbits, chickens, rats).
Complete one optional tomb.
Kill and loot 10 large animals (deer, boar, wolves).
In multiplayer, escape death 3 times by using the rope ascender.
Survive 10 explosions in multiplayer.
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.
Purchase a new multiplayer character.
Kill 2 multiplayer enemies with a single explosive.
Reach level 10 in multiplayer.
Catch a player in a snare trap in multiplayer.
Kill a zip-lining enemy player in multiplayer.
In multiplayer, be the only player on your team that isn't dead or downed.