Here is the full list of all 49 Metro 2033 Redux achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Find the truth.
Complete the game in Survival Mode.
Complete the level BLACK STATION without killing or knocking out any enemies.
Complete FRONTLINE level without killing anyone.
Save a group of Reds from Fascist captivity.
Knock 30 human enemies out in close combat.
Become a true ranger.
Complete the game in Spartan Mode.
Complete all 51 of Artyom's hidden Diary pages.
Kill 2 demons.
Kill 5 amoebas.
Kill 100 enemies with assault rifles.
Kill 10 Spiders.
Kill at least one enemy with each weapon available in the game
Kill 30 enemies with a flamethrower.
Kill a librarian.
Kill 50 Watchmen.
Drink at every occasion.
Exchange 500 Military-Grade 5.45 rounds at Exchange kiosks.
Kill 30 human enemies in close combat.
On the level OUTPOST reach the radio tower and broadcast the commander's message.
Use a Medkit 75 times.
Open 15 locked safe boxes.
Kill 20 lurkers.
Kill 100 enemies with shotguns.
Kill 30 enemies with flame grenades.
Kill 200 Mutants.
Disarm 15 wire traps.
On the level DEPOT silently kill the first guard and break into the Fascist station unnoticed.
On the level FRONTLINE kill all of the enemy Red Army and Fascist Soldiers.
Get 30 kills with Hellbreath.
Explode 30 enemies.
Kill 15 human enemies with Headshots from at least 30 meters' distance.
Kill 100 enemies using revolvers.
Save 1000 military-grade rounds.
Make 30 deals in weapon shops.
Blow up the tunnel and airlock at CURSED STATION.
Kill 100 nosalises.
Kill 100 Human Enemies.
Kill 50 humans with pneumatic weapons.
Kill 30 human enemies with headshots.
Find all Ranger stashes in Dead City.
Spend 60 seconds in a Radiation Hotspot.
Kill 30 enemies with throwing knives.
Stealthily kill 15 Enemies.
Kill 10 Enemies in a row without taking any damage.
Help the poor, a coin for the kid, medicine for the sick. You help everyone you see.
On the level HUNTER kill the nosalises before they break through the ventilation grilles.
Wipe your Gas Mask 20 times.