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.
Save D6.
Complete the game in Survival Mode.
Complete all 43 of Artyom's hidden Diary pages.
See all Visions in the Dead City.
Complete the BRIDGE level without a kill.
Remove your mask when Lesnitsky demands it.
Rescue the Women and Children on the BANDITS level without raising alarm.
Complete the REVOLUTION level without killing and raising an alarm.
Complete the FACILITY level without killing or raising alarm.
Complete the SEPARATION level without killing or raising alarm.
Finish the ASHES level without taking a hit.
Spend 1 hour on the DEVELOPER level.
Drink at every occasion.
Kill all armed enemies on the REVOLUTION level, including all reinforcements.
Kill the Watchmen attacking the Railcar without taking any damage.
Complete the ANNA level.
Complete the KHAN level.
Complete the PAVEL level.
Open 10 locked safe boxes.
Complete the SPIDER LAIR level.
Disarm 10 Traps.
Complete the TOWER level.
Complete the SNIPER TEAM level.
Complete the KSHATRIYA level.
Complete the HEAVY SQUAD level.
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.
Find out about the Reds' plans.
Kill the Rhino.
Kill 100 Mutants.
Spend 30 minutes' worth of Filters.
Kill 100 Human Enemies.
Find and return the crying child's Teddy Bear.
Make 10 Spiders flip belly-up.
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.
Burn 50 Cobwebs.
Use 10 Lever Switches.
Stealthily kill 15 Enemies.
Kill 10 enemies in a row with Throwing Knives.
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.