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.
Purchase a new multiplayer character.
Reach level 60 in multiplayer.
Incapacitate 25 enemies with dodge counter.
Shoot 10 enemies off zip lines.
Rope pull 5 enemies off edges.
Survive 10 explosions in multiplayer.
Win a ranked match in every multiplayer mode.
Complete a match in all multiplayer modes.
In multiplayer, escape death 3 times by using the rope ascender.
Kill 10 multiplayer enemies using your melee attack.
Kill 2 multiplayer enemies with a single explosive.
Revive a teammate in a multiplayer match.
Reach level 10 in multiplayer.
Kill 20 enemy players in multiplayer using a turret.
Kill a zip-lining enemy player in multiplayer.
Catch a player in a snare trap in multiplayer.
In multiplayer, be the only player on your team that isn't dead or downed.
Complete all challenges.
Fully mod and completely upgrade all weapons.
Find all documents, relics and GPS caches.
Complete the game.
Shoot a bundle of dynamite out of the air.
Find 75% of GPS caches.
Complete all optional tombs.
Collect 75% of all relics.
Fully mod and completely upgrade any weapon.
Purchase all skills in all categories.
Kill and loot 10 flying animals (crows and gulls).
Kill 40 enemies with the shotgun.
Loot 200 enemies.
Find 75% of all documents.
Collect 25% of all relics.
Kill and loot 10 small animals (rabbits, chickens, rats).
Find 25% of GPS caches.
Collect 5000 pieces of salvage.
Complete all conversations with the Endurance crew.
Purchase all skills in one category.
Kill 75 enemies with the rifle.
Kill FeeFee the crab.
Force an enemy to drop dynamite that kills two people when exploding.
Kill 35 enemies with the pistol.
Perform 15 finishers.
Kill 50 enemies with the bow.
Find 25% of all documents.
Perform 50 headshot kills in the single player campaign.
Kill 25 unaware enemies.
Complete one challenge.
Kill and loot 10 large animals (deer, boar, wolves).
Complete one optional tomb.