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