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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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?

The installer

8 years ago Full Version 4 comments

Download me to install the game

The Video Trailer

9 years ago Movies 0 comments

Check out the trailer with in game footage.

Post comment Comments  (0 - 10 of 76)
Guest Dec 25 2014 says:

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TheUnbeholden Jan 24 2015 replied:

every pre August 2010 mod has this issue, just google: Fixes for HL2 mods broken by the SteamPipe update.

+1 vote     reply to comment
rcminor Aug 12 2013 says:

Well it's getting late and I've discovered 2 of the endings. Pretty good overall, I did enjoy playing it for the most part. Agree that a couple of parts were over the top, the opening street battle is ridiculously hard, even on easy. I don't know if we're supposed to make use of the Combine rifle in the middle of the street near the gate, but it's too close if so -- the goons just swarm in to the sides where you can't shoot them, and you don't even see them move in. And it kinda made me uncomfortable that your first buddy there has to get shot before you can take the RPG and finish off the gunship. I played through that sequence more times than I can count, and I think I saw him get off one round -- once. Couple other remarks,I'll put them in the Review with a spoiler alert.

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Vanseth Feb 26 2013 says:

Good mod. I am waiting for 2. part

+1 vote     reply to comment
Crow727 Aug 20 2012 says:

So as far as I can tell, the teleport takes you into a parallel universe where Alyx is working together with Breen.
If you kill them both, the universe corrects itself by taking you back to your universe?
So that's my take on this mod anyway.

+1 vote     reply to comment
Skizzo Jun 20 2012 says:

Nice ideas, but poor execution: gameplay is sometimes confused and/or meaninglessly hard ("invincible" helicopter, Antlion Guard who cannot be hurt by shooting at it...), and the ending is pointless. Yes, you have four endings, but there's no clear connection between your actions and the outcome.
Technically good, but kind of "kiddie" gameplay (more action than brain).

+1 vote     reply to comment
locotto Mar 2 2011 says:

can i play this game whit ep1?

+1 vote     reply to comment
Null-Entity Feb 3 2011 says:

A wonderful short bought of action with some interesting twists on the HL2 characters/story opening.

+1 vote     reply to comment
kalidrone Jan 1 2011 says:

Extremely amazing idea and story, I LOVE IT, no lie! X3 Can you please tell me if there is a way to save Eli, Barney or Kleiner? I'd truly appreciate it. :)

+1 vote     reply to comment
kalidrone Jan 1 2011 replied:

Help me out here, from what I see on the comments here you can kill either Alyx/Breen at the ending scene but when I get there I have no weapons to kill them with, please tell me how to kill either because after Gordon exits the Teleport room I try to rush kill breen but it's like he isn't even receiving anything from what I fire at him, please help me out here, please. D:

+1 vote     reply to comment
kalidrone Jan 6 2011 replied:

YES! I managed to get the different endings! Now I know how to get them as well! X3 To all who are looking for the different endings in this story: Please be advised that after your brief meeting with Gman you should HIGHLY take heed of his Very Words because right when you load into the rooftop battle Alyx Vance and Wallace Breen make a break for it and it's up to you to see who you will kill be be warned as there are some deadly Combine Elites loosely guarding them but there's only around 2-3 at most and THAT's when you can decide what ending you want, just wanted to say this for all of you frustrated and confused on how to get the different ending as I was, truly! XP lol So you must move with as much haste as possible while staying alive from the Combine Elites while taking either Breen/Alyx out, good luck. :)

+1 vote     reply to comment
kalidrone Jan 6 2011 replied:

Also I just want to say that this reminds me A LOT of Breakdown with Derrick changing the time line, so this is such an awesome story, thank you for this, it has made me very happy. XD

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Released 2007
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Causality Effect
Last Update
8 years ago
92 members