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.
Destroy D6.
Complete the game in Survival Mode.
Kill Pavel.
See all Visions in the Dead City.
Disarm 10 Traps.
Complete the REVOLUTION level without killing and raising an alarm.
Complete all 43 of Artyom's hidden Diary pages.
Complete the SEPARATION level without killing or raising alarm.
Finish the ASHES level without taking a hit.
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.
Find and return the crying child's Teddy Bear.
Drink at every occasion.
Rescue the Women and Children on the BANDITS level without raising alarm.
Kill the Watchmen attacking the Railcar without taking any damage.
Kill all armed enemies on the REVOLUTION level, including all reinforcements.
Open 10 locked safe boxes.
Turn off 40 Lights without breaking them.
Escape from the Red Line.
Watch the entire Theater Show.
Complete the ECHOES level undetected by the Watchmen.
Make 10 Spiders flip belly-up.
Complete the FACILITY level without killing or raising alarm.
Stealthily kill 15 Enemies.
Escape the chasing Nazis on the REICH level without being caught once.
Free the Prisoners.
Complete training sequence.
Complete the HEAVY SQUAD level.
Complete the PAVEL level.
Complete the ANNA level.
Complete the KHAN level.
Kill 100 Mutants.
Use 10 Lever Switches.
Complete the SPIDER LAIR level.
Burn 50 Cobwebs.
Complete the SNIPER TEAM level.
Spend 30 minutes' worth of Filters.
Complete the KSHATRIYA level.
Complete the TOWER level.
Kill 100 Human Enemies.
Kill 10 enemies in a row with Throwing Knives.
Spend 1 hour on the DEVELOPER level.
Choose three primary weapons that use different ammo.