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