Here is the full list of all 49 Metro: Last Light Redux achievements. It takes around 30-35 hours to unlock all of the achievements on Windows.
Complete the game in Survival Mode.
Complete all 43 of Artyom's hidden Diary pages.
Complete the KSHATRIYA level.
Complete the TOWER level.
See all Visions in the Dead City.
Watch the entire Theater Show.
Drink at every occasion.
Kill all armed enemies on the REVOLUTION level, including all reinforcements.
Spend 1 hour on the DEVELOPER level.
Destroy D6.
Kill the Watchmen attacking the Railcar without taking any damage.
Finish the ASHES level without taking a hit.
Stealthily kill 15 Enemies.
Kill Pavel.
Kill 100 Human Enemies.
Complete the ANNA level.
Complete the KHAN level.
Complete the SPIDER LAIR level.
Complete the PAVEL level.
Open 10 locked safe boxes.
Kill 10 enemies in a row with Throwing Knives.
Disarm 10 Traps.
Complete the SNIPER TEAM level.
Complete the HEAVY SQUAD level.
Save D6.
Complete the game in Spartan Mode.
Make Moskvin tell the truth with help from the Dark One.
Save the Bear from the Watchmen after the fight.
Find out about the Reds' plans.
Complete the BRIDGE level without a kill.
Remove your mask when Lesnitsky demands it.
Kill the Rhino.
Kill 100 Mutants.
Spend 30 minutes' worth of Filters.
Find and return the crying child's Teddy Bear.
Rescue the Women and Children on the BANDITS level without raising alarm.
Complete the REVOLUTION level without killing and raising an alarm.
Make 10 Spiders flip belly-up.
Escape from the Red Line.
Complete the ECHOES level undetected by the Watchmen.
Burn 50 Cobwebs.
Complete the FACILITY level without killing or raising alarm.
Use 10 Lever Switches.
Turn off 40 Lights without breaking them.
Complete the SEPARATION level without killing or raising alarm.
Escape the chasing Nazis on the REICH level without being caught once.
Free the Prisoners.
Complete training sequence.
Choose three primary weapons that use different ammo.