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