Metro 2033 Redux

The Heavy Reader achievement is earned by killing one of the mutant creatures of the now apocalyptic Moscow named librarians which resemble Apes on the level Depository.
First thing you should know is that these things are the ground version of demons except can actually be hit much easier but still hurt when they hit you which (on normal) can get you all the way down in the low health state so be carefull to avoid that.
A second thing you should be aware of is that they are bullet sponges and will take quite abit of ammo to take down, so make sure you have your guns reloaded and air filter changed before taking on one of these!

Now we have that sorted let's start the guide!
When you enter the level depository, you will see the big hulking ape laying there looking away from you down the stairs. First things first, use either a sticky bomb or flame grenade and get the first hit on it, then you can easily train it around the stone pillars in the room but it make decide to run up the hole above you, if it does this keep shooting it and it will come back and fight you. It's best to do this on the very first one as the ones later on in the level have another one around them which isn't ideal since one of them can near one hit you and dry up all your ammo.

I hope this guide has helped, if there is anything wrong please let me know in the comments and I will change what needs to be changed

This is the most easy Achievement in the game if done right.

HAVE A FIREGRENADE READY.

As soon as you enter the Level after the Library there is one right in front of you in the middle of the room. Throw the firegrenade at him from safe distance, watch him burn to death.

And thats it.

Using the walkthrough provided on here by SwelterinBeaver, Vitiated1, and LifeExpectancy, I got this using only 2-3 grenades. Soon as Depository starts, you will see a Librarian with it's back to you ahead on a lower floor section. Quickly select grenades by holding and using the to select your choice of grenades (I used regular ones) and then use to pelt the sucker with your grenades. The Librarian should go down in about 2 hits.

Good hunting!