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