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