Welcome to Achievement guide for 100% completionist. There was no such a guide on internet so i though it would be a good idea to post one.
First of all I'm sorry if there is any mistake in text. English is not my main language.

Achievements in this game are pretty easy so it should't be a problem to complete them all. You can do all of them in one playthrough but it's very hard so i recommend you to play it at least twice. One playthrough play on Smart and Resourceful, Rite of Passage or One with the Jungle and 2nd play on Deadly Obsession. I recommned doing all achiev. with enemies on lower difficulty because it's a lot easier.

Path of the Stars
Decipher the Path of the Stars
Story related, cannot be missed.

Día de Muertos
Remove the dagger from the Temple of the Moon
Story related, cannot be missed.

Recipe for Disaster
Survive the flood
Story related, cannot be missed.

Survival Instincts
Defeat the Empress Jaguar
Story related, cannot be missed.

Fire of Life
Enter the Temple of Life's inner chamber
Story related, cannot be missed.

The Hidden City
Find Paititi
Story related, cannot be missed.

The Underworld
Get out of the Cenotes alive
Story related, cannot be missed.

New Heights
Complete a climb using found Overhang Climbing Gear
Story related, cannot be missed.

Family Ties
Free Unuratu from prison
Story related, cannot be missed.

Heart of the Serpent
Find the mission of San Juan
Story related, cannot be missed.

The Chosen One
Find the Silver Box of Ix Chel
Story related, cannot be missed.

Back to Where We Started
Return to Paititi
Story related, cannot be missed.

Queen of the Damned
Make an unlikely ally
Story related, cannot be missed.

Quite the Adventure
Complete the Game
Story related, cannot be missed.

Smart and Resourceful
Complete Shadow of the Tomb Raider on Smart and Resourceful difficulty
Just finish game

Rite of Passage
Complete Shadow of the Tomb Raider on Rite of Passage difficulty
Just finish game

One with the Jungle
Complete Shadow of the Tomb Raider on One with the Jungle difficulty
Just finish game

Deadly Obsession
Complete Shadow of the Tomb Raider on Deadly Obsession difficulty
This difficulty may be a little harder, because you can save game only at camps, which could be sometimes very frustrating. Just be a little more careful and you should be OK. You will get all previous difficulty achievements after completed this one.

All achievements related to enemies are MISSABLE, after you finish main story no enemies will spawn so be careful.

Look, Over There!
Kill 3 enemies while they are distracted
You'll probably get this on your first playthrough...

First Blood
Perform a Stealth Takedown from a mud-covered wall
You'll probably get this on your first playthrough...

Like a Shadow
Stealth Takedown 25 enemies
You'll probably get this on your first playthrough...

Turned Tables
Kill 5 enemies while they are searching for Lara
You'll probably get this on your first playthrough...

Playing with Fire
Burn 2 enemies simultaneously
Best spot for this is at the start of the game. This is the spot:











Marksman
Perform 20 headshots with the bow
You'll probably get this on your first playthrough...

Last Known Position
Lose the enemy 10 times
You'll probably get this on your first playthrough...

Total Party Kill
Kill 5 enemies with friendly fire
After you leave paitti you'll find new type of an arrow, just shoot few enemies with it and let them kill everybody around them

Chain Gang
Perform the Serpent's Fury 3 times
You have to purchase SERPENT'S FURY skill and perform stealth takedown on two enemies near each other

Surprise!
Perform 5 Eagle's Talon Takedowns
You'll probably get this on your 2nd playthrough...Try to use it everytime u can or reload checkpoints











Gunslinger
Perform 3 headshots in 3 seconds with the pistol
Best spot for this is at the start of the game. This is the spot:











Sixth Sense
Hunt and kill 10 enemies while Perception is active
I recommend you to start doing this right after you find out recipe fo mixture.
You have to kill 10 enemies in stealth with Perception mixture active.

In the Moment
Kill 10 enemies while Focus is active
I recommend you to start doing this right after you find out recipe fo mixture.
You have to be in fight and kill 10 enemies with Focus mixture active.

Made to Endure
Takedown 10 enemies while Endurance is active
I recommend you to start doing this right after you find out recipe fo mixture.
You have to perform stealth takedown on 10 enemies with Endurance mixture active.

All collectibles can be collected after main story

Treasures from the Past
Decipher a Monolith
You will learn new language by collecting documents and artifacts. After that u can decipher a monolith.
Help thy Neighbor
Complete a Side Mission
There are videos on Youtube on how to get them all

Unwelcome Guests
Get rid of the pillagers outside of Kuwaq Yaku
First side mission. There is almost no way to miss this one.

Hearts and Minds
Retrieve Manko's Necklace
Side quest in paitti

I Believe Hakan Fly
Rescue Hakan from the cultist
Right before you go safe Unuratu

Beast of Legend
Defeat the Nahual
Last side quest, It will show up after you come back to paitti and have all previous side quests completed

Archeologist
Complete an Artifact Collection
There are videos on Youtube on how to get them all

Stele Hunter
Complete 3 Challenge Tombs
Find more in Tomb Raider

Resting Places
Uncover 3 Crypts' secrets
Here is a video with all crypts and where to find them:











Up to the Challenge
Complete 5 Challenges
You can find all challenges and how to do them on Youtube

Underwater Archeologist
Collect 5 underwater Artifacts
There are videos on Youtube on how to get them all

Tomb Raider
Complete all main game Challenge Tombs
Here is a video with all tombs and how to solve them:











Treasure Hunter
Find and open all the Conquistador treasure chests
Here is a video with all chests and where to find them:











Dr. Croft
Complete all Artifact Collections
There are videos on Youtube on how to get them all

Completionist
Reach 100% completion
You must have all collectibles and finished story

On the Go
Craft special ammunition 50 times
Self explanatory

Makeshift Arsenal
Fully upgrade a weapon
Self explanatory

First Steps
Purchase a Skill
Self explanatory

Specialized
Earn all skills in one category
Self explanatory

Zoologist
Collect 20 critters
You need skill called OWL'S MEAL. You can find critters everywhere, so just play and kill them when you see them. There is no need to go look for them they will show up at some point.
Legendary Hunter
Hunt 5 rare animals
People in town will tell you where u can find them, you can also wear an outfit to higher your chances at finding them.

Good Samaritan
Complete 8 Side Missions
You can see them on your map. Some of these side missions can be missed. Make sure you finished them before continuing story.

• 1x Mission in Kuwak Yaku
  
• 6x Missions in Paititi
  
• 1x Mission in San Juan

Asking Price
Buy an item from a merchant
Just buy something from merchant. They are in every town.

Untold Riches
Gather 40 gold ore
Self explanatory

Point of Interest
Learn of 5 interesting locations from civilians
Just talk to people and they will tell you something about animals, crypts or tombs.

Better Equipped
Get 3 pieces of equipment
You can buy equipment from merchant.

That's a Knife!
Fully upgrade the Makeshift Knife
There are 2 upgrades that you need to get:

1.First is in Paitti, one of merchants there is selling it
2.2nd is reward for side quest (I Believe Hakan Fly)

Thread the Past
Restore 5 vestige outfit pieces
You'll get them in crypts and then just go to camp fire, outfits and restore them

To the Nines
Restore and equip a matching vestige outfit
Restore and wear same type of outfit on upper and lower body

Como Te Llama
Pet 5 llamas
They are all over Hidden city, just walk around you should find at least 5 of them

Thanksgiving
Shoot a turkey with a Flare Round
First u need skill called SERPENT'S GLINT, if you have that skill just travel to San Juan to the Ruined Tower and kill turkey with flare.

Destiny's Trialed
Complete the Forge of Destiny Challenge Tomb
Self explanatory

Heir Born
Complete the Echoes of the Past Side Mission and discover Abby’s ancient origins
Side mission is unlocked after completing "The Trial of The Eagle" mission.

Bleeding Edge
Obtain the Grenadier Skill, equip the Umbrage 3-80 Shade weapon, and Brocken Shadow outfit
After finishing Abby's side mission go to nearest campfire and equip newly obtained outfit
and rifle after leaving camp you shoud get the achievement.

Echoes of the Fast
Obtain a Bronze, Silver, or Gold medal in Time Attack for the Forge of Destiny Challenge Tomb
Self explanatory

Echoes of the Furious
Obtain a Bronze, Silver, or Gold medal in Score Attack for the Forge of Destiny Challenge Tomb
Self explanatory

That Was A Breeze
Complete the Path of Huracan Challenge Tomb
Self explanatory

Go With The Flow
Complete The Age Makers Side Mission
Side mission is unlocked after completing "Find the Rebel Cave" mission.

Eyes Of The Storm
Obtain A Thousand Eyes skill, equip elite versions of Oathtaker's Bow and Sinchi Chiqa Battle Dress
After finishing side mission go to nearest campfire and equip Oathtaker's Bow and Sinchi Chiqa Battle Dress - Honor Guard, after leaving camp you shoud get the achievement

Float Like A Butterfly
Obtain a Bronze, Silver or Gold medal in Time Attack for the Path of Huracan Challenge Tomb
Self explanatory

Sting Like A Bee
Obtain a Bronze, Silver or Gold medal in Score Attack for the Path of Huracan Challenge Tomb
Self explanatory

Monkey Do
Complete the Howl of the Monkey Gods Challenge Tomb
Self explanatory

Harmony
Complete the Path of Fear Side Mission
Side mission is unlocked after reaching San Juan & completing "Retrieve the king's horn" side mission.

Creature Comforts
Obtain White Breath skill, equip Griff of Fear White Knuckle and Scales of Q Feathered Serpent
After finishing Uchu's side mission go to nearest campfire and equip Griff of Fear White Knuckle and Scales of Q Feathered Serpent after leaving camp you shoud get the achievement

Howl Long
Obtain a Bronze, Silver, or Gold medal in Time Attack for the Howl of the Monkey Gods Challenge Tomb
Self explanatory

Organ Grinder
Obtain a Bronze, Silver or Gold medal in Score Attack for the Howl of the Monkey Gods Challenge Tomb
Self explanatory

Mushroom With A View
Complete the Sixth Seal Challenge Tomb
Self explanatory

He Ain't Heavy
Complete the Dragon and the Prince Side Mission


Dressed For Success
Obtain the Raptor's Eye skill, equip the Silent Sting Scorpion weapon and Hunter's Array Apex outfit
After finishing side mission go to nearest campfire and equip Silent Sting Scorpion and Hunter's Array Apex outfit after leaving camp you shoud get the achievement

Cannonized
Obtain a Bronze, Silver, or Gold medal in Score Attack for the Sixth Seal Challenge Tomb
Self explanatory

Go Cart
Obtain a Bronze, Silver, or Gold medal in Time Attack for the Sixth Seal Challenge Tomb
Self explanatory

Hydro Power
Complete the Slayer's Gauntlet Challenge Tomb
Self explanatory

Whole World Blind
Complete The Two Graves Side Mission
To unlock side mission, you have to complete I Believe Hakan Fly Side mission.

Spoiled For Choice
Obtain Divine Bounty skill, equip Serpent Lash Godslayer weapon and Dragon Scales Legend outfit
After finishing side mission go to nearest campfire and equip Serpent Lash Godslayer weapon and Dragon Scales Legend outfit, after leaving camp you shoud get the achievement.

Go Fish
Obtain a Bronze, Silver, or Gold medal in Score Attack for the Slayer's Gauntlet Challenge Tomb
Self explanatory

Rapids
Obtain a Bronze, Silver, or Gold medal in Time Attack for the Slayer's Gauntlet Challenge Tomb
Self explanatory

Caiman Conquered
Complete the Zipacna's Craving Challenge Tomb
Self explanatory

Leaping Lizards
Complete The Wrathful God Side Mission
To unlock side mission, you have to complete all main quests in San Juan

Ready To Rumble
Obtain the Volcano Skill, equip Whispering Scourge Pandemic weapon and Reptile Hide Leviathan outfit
After finishing side mission go to nearest campfire and equip Whispering Scourge Pandemic weapon and Reptile Hide Leviathan outfit, after leaving camp you shoud get the achievement.

Zip It
Obtain a Bronze, Silver, or Gold medal in Time Attack for the Zipacna's Craving Challenge Tomb
Self explanatory

Offshore Count
Obtain a Bronze, Silver, or Gold medal in Score Attack for the Zipacna's Craving Challenge Tomb
Self explanatory

Put Herself Together
Complete the Mother Protector Challenge Tomb
Self explanatory

Moonlight Sonata
Complete the Eternal Reward Side Mission
To unlock this side mission, you have to complete game and the first DLC - The Forge

Moonlit Knight
Obtain Magic Touch Skill, equip Silver Strike Moonbeam weapon and Midnight Sentinel Farseer outfit
After finishing side mission go to nearest campfire and equip Silver Strike Moonbeam weapon and Midnight Sentinel Farseer outfit after leaving camp you shoud get the achievement.

Chel Game
Obtain a Bronze, Silver, or Gold medal in Time Attack for the Mother Protector Challenge Tomb
Self explanatory

Chak Attack
Obtain a Bronze, Silver, or Gold medal in Score Attack for the Mother Protector Challenge Tomb
Self explanatory

Seasoned Pro
Complete all 7 downloadable content missions and receive the Tunic of the Shorn One
Self explanatory

Good luck in collecting achievements. I hope this guide helped you a little bit, if yes then you can give it a thumbs up so everybody can see how to collect everything.

I took inspiration from The Horror Network.
All videos added in this guide are made by someone else.
Videos are from PowerPyx, GuideRanx, Game Guides Channel.