Cthulhu is a single-player modification for Half-Life.
It contains 65 maps, 21 new monsters and 14 new weapons.

Aeons ago, Earth was ruled by The Great Old Ones, beings so alien and terrible that merely seeing them would drive most people mad. Before man's ancestors climbed down from the trees, these being were defeated in a war with The Elder Gods.
But their alien nature meant that they could not be slain in any way that we would understand, so they were imprisoned.
And so they wait, patient and potent until the stars are right and they shall walk forth once again and wipe mankind from the face of the Earth.
You play Ranulf Stafford, an occult investigator in Arkham in the year 1928. Drawn into a nightmare chain of events, you find yourself the only thing standing between mankind and the return of Cthulhu, one of the most dreadful of The Great Old Ones.

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The Miskatonic University library Outside the city of the Great Race of Yith The archaeological dig
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Cthulhu v1.0 Installer

Cthulhu v1.0 Installer

Feb 23, 2006 Full Version 8 comments

This is the installer for Cthulhu: An Unspeakable Mod for Half-Life v1.0

Cthulhu v1.1 Patch

Cthulhu v1.1 Patch

Feb 23, 2006 Patch 4 comments

This is the v1.1 Patch for Cthulhu: An Unspeakable Mod for Half-Life

Post comment Comments  (60 - 70 of 107)
CdeathJD Jul 22 2009, 2:45pm says:

Looks good, but has a game-breaking bug... after visiting the mansion in the woods and returning to your car, whatever level change is supposed to go off... doesn't!

+2 votes     reply to comment
CdeathJD Jul 22 2009, 3:12pm replied:

Oh, it seems the level change isn't the car itself, but in the bushes at the other side of it, omgwtfbbq!

+1 vote     reply to comment
jesusmora May 21 2009, 7:59pm says:

i have a problem with the mod, this shutdown the game in the start, in software, opengl and direct mode.

+1 vote     reply to comment
freakybunnies Jan 29 2009, 9:50pm says:

Looks great!

+1 vote     reply to comment
Jigron Jan 10 2009, 5:34pm says:

where d owe extract it

+1 vote     reply to comment
Johnchief117 Dec 25 2008, 10:48pm says:

okay, i downloaded the mod but i dont know how to get it to work, even after reading the readme.

+1 vote     reply to comment
Ekonk Apr 18 2009, 5:29pm replied:

You've got to make a new folder in that one of your Steam folders where all those other games are. Half-life 2, team fortress etc etc. In that folder, you have to make a new one named Half-Life. In that folder you make a new one called Cthulhu. Install there, and voila.

+1 vote     reply to comment
ditpet Dec 11 2008, 2:11pm says:

hi, how can I kill Dagon (big green creature in the warehouse at the docks) please help me, my magic power (next to my HP) is very low, and the dynamites didn't hurt him/her.
I read the alkthrough but I didnt understand it.

+1 vote     reply to comment
DanteXVII Dec 7 2008, 10:14am says:

A high definition pack would be fine !!!!

+1 vote     reply to comment
phipe Jul 12 2008, 4:56pm says:

I really liked this mod when i played it, last years easter. I spended the week playing and i enjoyed it. i can say that the Ghouls Lair was the scariest part.

+1 vote     reply to comment
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Release Date
Released Feb 23, 2006
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87 votes submitted.

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Highest Rated (5 agree) 10/10

An incredible mod from start to finish.

Among my favorite half-life mods of all time. :)

Jun 7 2011, 2:20pm by flippedoutkyrii

Lowest Rated (2 agree) 1/10


Apr 1 2013, 7:13am by Urby

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Cthulhu Cthulhu
Last Update
9 years ago
94 members