What if everything that went wrong on "A Red Letter Day" was not caused by what you thought? What if your teleport ripped a hole in space and time? Now you must travel through time to correct the events and set right your past.

Causality Effect
A Red Letter Day Gone Wrong

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0 comments by OnboardError on May 26th, 2006

Causality Effect has been updated. I have fixed and changed little bugs found in the mod after its release. In other news the mod will be aired in PC Games magizine this month and will be on a DVD disc that comes with your magizine.

Causality Effect
?A Red Letter Day Gone Wrong?

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The installer

The installer

May 7, 2007 Full Version 4 comments

Download me to install the game

The Video Trailer

The Video Trailer

May 26, 2006 Movies 0 comments

Check out the trailer with in game footage.

Post comment Comments  (10 - 20 of 74)
superstepa Nov 22 2010, 5:42am says:

Doh , In the beginning , when there is a combine door , and a combine "Plane" flies , I alwayshet killed , because this rebel CANT KILL THIS DAMN THING

+1 vote     reply to comment
megaman951 Sep 4 2010, 10:54pm says:

hmmm when I start the mod Alyx just stands there...I assume this is because of the huge update they did to HL2 ?

+1 vote     reply to comment
MizoreJedi Jul 19 2014, 1:27pm replied:

The same thing happens to me, when I write the first map in the console, because if I go to New Game, the game returns to the menu.

+1 vote     reply to comment
ninjatwork Jul 4 2010, 2:46am says:

This was one of the best mods I've ever played in respect to the HL2 story line. I don't even know what else to say other than that I gave it a 10.

Oh, and I appreciate the small download size too. =D

+1 vote     reply to comment
johnnyB96000 Jul 6 2010, 11:46am replied:

Did anyone notice that if you draw in a Big black zombie thing into a barnacle the game always crashes, i guess this is due to the fact there is no sprite or sequence in the game so as to which the zombie dies in this way. Nor is there in HL2 to my knowledge

+1 vote     reply to comment
Rallymen007 Dec 25 2009, 12:16pm says:

Just finished this mod, and I really enjoyed playing. Mapping is nice, cut scenes are good, but the timeline is kind of weird, all those teleports confused me :)

But, how do you get other endings ?

+1 vote     reply to comment
ig Feb 28 2010, 3:06am replied:

Yuo kill breen or alyx or both or neither

+1 vote     reply to comment
PsiKO911 May 13 2010, 9:41am replied:

OK but how do you kill them?

+1 vote     reply to comment
johnnyB96000 Jul 6 2010, 11:44am replied:

you just run up to them at the last scene and shoot them with a shotgun as quick as possible, both one or the other or none gives 4 possible endings.

+1 vote     reply to comment
babadiboopi Dec 18 2009, 2:43pm says:

i greatly enjoyed this mod. it had some awesome level design and gameplay and i thought the whole concept was fascinating and well executed, especially with how Alyx is evil instead of good; it was crazy how you could kill her!

+3 votes     reply to comment
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Released May 7, 2007
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Causality Effect
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Last Update
7 years ago
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