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  (50 - 60 of 76)
Fiasco Jan 23 2007 says:

This mod has an excellent sense of pace, scale and imagination. I played it all the way through immediatly after installing it. I think I enjoyed it more than HL2 itself! It combines story line with action in a well balanced cocktail that keeps you pushing on. A few simple puzzles serve to slow the game before launching you into the best HL2 fire-fights I have been involved in. It captures that old school 'boss' feeling in the set-pieces, particularly at the end, and multiple endings inspire you to play it through again. Not to mention the slightly tongue in cheek humour :) All round one of the best mods I have played ever. And done by one guy... ?!

Anyone for a free HL2 expansion pack?!?! Hit the download tab!

"Thanks for the Mod" is all I can say.

+1 vote     reply to comment
Kodox Jan 11 2007 says:

Simply outstanding. This mod is a work of pure art and creativity.

+1 vote     reply to comment
Naikei Dec 29 2006 says:

Torrent available from:

+1 vote     reply to comment
Lucífer Dec 25 2006 says:

So this is like the Half-Life 2 version of Timesplitters Future Perfect???
But I'm guessing ALOT better :D

+1 vote     reply to comment
Lazyeye Dec 12 2006 says:

Simply a great story!

+1 vote     reply to comment
exelero Nov 9 2006 says:

yeah i totally consent with alfaalex101 :D felt a bit sorry first, but then shot alyx too great mod btw

+1 vote     reply to comment
DOAmaster Sep 30 2006 says:

The mod is action packed and loads of fun, if you are reading this and have not played it yet stop reading and play it.

+1 vote     reply to comment
Flying-Q Apr 4 2007 says:

I'm really enjoying this but I'm stuck at the Ant Lion in the sewer. I have tried jumping to the ledge to the left and can't seem to make it.

I've unloaded all my ammo at the ant lion and it just sits there snarling at me

I saw a pic on onboarderror's site that shows the view of this part from the otherside of the grating and there is a bent hole in the grating so I tried throwing a fuel drum at that area using GravGun but that had no effect, nor does grenades. I've tried getting the ant lion to chase me to that area hoping it will bash the hole but still no joy, even when jumping, running, crouching or any combination of those.

I also tried running through the flames at the right but I just burn to a crisp.

I'm stuck and I really want to move on as this mod has me on the edge of my seat.


+1 vote     reply to comment
ratcat Sep 28 2006 says:

Thank you. Believe me, that`s excessive praise from me. I have a folder full of mods for all sorts of games and this is in the top Ten. Absolutely superb in every way. I enjoyed it all the way and I didnt find it too hard but challenging as a game should be. What a great twist on HL2 and what an imagination you have! Keep up the great work and again thank you for a free good two hours or more of additional game play to HL2. How the hell do you guys do it? In this particular mod you used the same maps from half-life 2 which to me is extraordinary, to be able to make a whole new episode whilst keeping the HL2 feel, well...that`s just great.It must take so much patience which I really admire, especially since you do it for nothing but the glory of being a succesfull modder, and that you are. Triple Elephant stamps and ultra Kudos to you and keep at it. If you can do something like this I believe anything is possible. Regards. RATCAT.

+1 vote     reply to comment
Search Oct 2 2006 says:

How do i install this thing????

+1 vote     reply to comment
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Half-Life 2
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Released 2007
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Causality Effect
Last Update
8 years ago
92 members