Armor and Stealth suits...
	Easy "DJ Artyom" achievement...
	Extending filter...
	Nightvision goggles...
	S.T.A.L.K.E.R. series referenc...
	Various Steam Achievements...

Before entering the train car at Armory Station, you can purchase a Stealth Suit for 100 military cartridges from the vendor across from the Ammo Exchange. There is a vendor next to that one that sells an Armor Suit that decreases damage. Both suits an be worn simultaneously. A similar Armor Suit is also sold by a vendor next to the Ammo Exchange in Polis.

There is an objective in "Outpost" regarding an S.O.S. message from "Defense". Go to the first Nazi controlled building, where a Demon snatches a fleeing Nazi, and fight through the area until reaching the upper level of that building. Find a hallway with three tripwire mines and two Demons. Get past the mines, then check the right room at the end of the corridor to find a ramp that provides access to the rooftop. You will find a corpse with a Kalashnikov on the rooftop. The communications apparatus for the achievement can be found in the corner of the rooftop.

Avoid jumping and sprinting to extend the use of your filter.

In addition to buying the Sneaking Suit at the Armory Station, you can get a pair of nightvision goggles at Front Lines. While in control of Artyom, turn around, and follow the train tracks. The nightvision goggles will be in a red breaker box guarded by two soldiers.

While in the Library, the two rangers will say the titles of several books. One of them is "Roadside Picnic" (1977) by the Strugatsky brothers, which is the book that Andrei Tarkovsky's 1979 movie "STALKER" was based on, which then was the inspiration behind S.T.A.L.K.E.R.: Shadow Of Chernobyl. The first person you can talk to resembles a "loner" Stalker and says "Take it easy bro!". The scene with the campfire with the guitar. The winter mask that are on dead people.

Complete the indicated task to unlock the achievement.

Achievement	How to unlock
Air Bender	Kill 50 humans with pneumatic weapons.
Blogger	Complete all 51 of Artyom's hidden Diary pages.
Cowboy	Kill 100 enemies using revolvers.
Demolitionist	Blow up the tunnel and airlock at CURSED STATION.
DJ Artyom	On the level OUTPOST reach the radio tower and broadcast the commander's message.
Enlightened	Find the truth.
Fire in the hole	Kill 20 lurkers.
Fire!	Kill 30 enemies with flame grenades.
Generous	Help the poor, a coin for the kid, medicine for the sick. You help everyone you see.
Gunman	Kill 100 enemies with shotguns.
Heavy Reader	Kill a librarian.
Hedge-hopper	On the level FRONTLINE kill all of the enemy Red Army and Fascist Soldiers.
Hunter	Kill 200 Mutants.
If it's hostile, you kill it.	Become a true ranger.
Inquisitor	Kill 2 demons.
Invisible man	Complete FRONTLINE level without killing anyone.
Ka-Boom!	Explode 30 enemies.
Manhattan Project	Spend 60 seconds in a Radiation Hotspot.
Marksman	Kill 15 human enemies with Headshots from at least 30 meters' distance.
Merciful	Complete the level BLACK STATION without killing or knocking out any enemies.
Metro Trader	Make 30 deals in weapon shops.
Ninja	Kill 30 enemies with throwing knives.
Nosalis hunter	Kill 100 nosalises.
Pathoanatomist	Kill 5 amoebas.
Pyro	Kill 30 enemies with a flamethrower.
Quick Draw	On the level HUNTER kill the nosalises before they break through the ventilation grilles.
Raider	On the level DEPOT silently kill the first guard and break into the Fascist station unnoticed.
Ranger	Find all Ranger stashes in Dead City.
Rescue Ranger	Save a group of Reds from Fascist captivity.
Scrooge	Save 1000 military-grade rounds.
Shocking	Get 30 kills with Hellbreath.
Slice & Dice	Kill 30 human enemies in close combat.
Snake	Stealthily kill 15 Enemies.
Sniper	Kill 30 human enemies with headshots.
Soft Touch	Disarm 15 wire traps.
Spartan 2033	Complete the game in Spartan Mode.
Spider hunter	Kill 10 Spiders.
Stunning	Knock 30 human enemies out in close combat.
Survivor 2033	Complete the game in Survival Mode.
Tank	Kill 10 Enemies in a row without taking any damage.
Thief	Open 15 locked safe boxes.
Toast!	Drink at every occasion.
Tonic Man	Use a Medkit 75 times.
Trigger Happy	Kill 100 enemies with assault rifles.
Warrior	Kill 100 Human Enemies.
Watchman hunter	Kill 50 Watchmen.
Weaponsmith	Kill at least one enemy with each weapon available in the game
Wheeler-Dealer	Exchange 500 Military-Grade 5.45 rounds at Exchange kiosks.
Who goes there?	Wipe your Gas Mask 20 times.