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