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