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.
Watch the entire Theater Show.
Remove your mask when Lesnitsky demands it.
Make 10 Spiders flip belly-up.
Save the Bear from the Watchmen after the fight.
Complete the SPIDER LAIR level.
Complete the KHAN level.
Burn 50 Cobwebs.
Complete the ECHOES level undetected by the Watchmen.
Kill 10 enemies in a row with Throwing Knives.
Drink at every occasion.
Complete the BRIDGE level without a kill.
Complete the FACILITY level without killing or raising alarm.
Complete the PAVEL level.
Complete the ANNA level.
Complete the SNIPER TEAM level.
Spend 1 hour on the DEVELOPER level.
Destroy D6.
Complete the game in Spartan Mode.
Make Moskvin tell the truth with help from the Dark One.
Kill Pavel.
Find out about the Reds' plans.
Turn off 40 Lights without breaking them.
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.
Kill the Watchmen attacking the Railcar without taking any damage.
Kill all armed enemies on the REVOLUTION level, including all reinforcements.
Kill 100 Human Enemies.
Stealthily kill 15 Enemies.
Use 10 Lever Switches.
Escape from the Red Line.
Choose three primary weapons that use different ammo.
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.
See all Visions in the Dead City.
Disarm 10 Traps.
Complete the SEPARATION level without killing or raising alarm.
Complete the REVOLUTION level without killing and raising an alarm.
Complete all 43 of Artyom's hidden Diary pages.
Save D6.
Complete the game in Survival Mode.
Open 10 locked safe boxes.
Complete the KSHATRIYA level.
Complete the HEAVY SQUAD level.
Complete the TOWER level.