Rune Locations (Image/Text)

For completionist purposes.

Beginning of the End / Argent Facility

First Rune

Here's the first rune, easily visible as soon as you exit the indoor area you spawn in.

Second Rune

Get over that protuberance and remember that landmark, you'll be going there.
Reach A - you'll now be seeing the second image. Go into the jump pad and there'll be a door in front of you when you land, go through it.
From the top of the landmark, go down and enter that door. From there just follow the path on the second image.

Argent Tower / Argent Energy Tower

Third Rune

Go to the entrance, from which you can see the rune, then follow the path to reach it.

Fourth Rune

Get to A, then follow the path in the second panel.
At the end of this path you'll see the rune to your left.

Into the Fire / Kadingir Sanctum

Fifth Rune

Before you can get this one you first need to get the Yellow and Blue skulls.
Hop down and look to the left. You'll see the first following image:
Follow this path and the rune will be right to your left.

Sixth Rune

After going through the Blue Door, fighting the enemies in that area, and going through the now-unlocked giant door, the rune will be right ahead.

Hell on Mars / Argent Facility (Destroyed)

Seventh Rune

As soon as you exit the airlock, go to the right and hop onto a crate. You can see the rune from here.

Eight Rune

We see this one at the start of the level but only get to it near the end.
Just play until you finish the fighting area that has the electrified water-flooded room.
After exiting it, turn to the left and it'll be there.

A Brighter Tomorrow / Advanced Research Complex

Ninth Rune

After talking to Samuel Hayden, go down the elevator, exit the airlock and activate the terminal.
The door to the rune will be open.

Tenth Rune

After acquiring the BFG and activating the terminal, the rune will be on the right.

Lazarus / Lazarus Labs

Eleventh Rune

After grabbing the Weapon Mod Drone upgrade, follow the corridor until you see a red door to your left. Look down and press E (interact button) - the rune will be on the other side.

Twelfth Rune

After shutting down the portal and going through one of the two corridors behind the terminal you interacted with, follow this path.

Congrats!

That was the last one. You got them all.
Rejoice!

[PerturbedxTirade]

I like the arrows

[Nescius]

@DV ty for the heads up. Hope it was useful.

[DV]

you labeled "sixth" twice