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