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  (60 - 70 of 74)
Tyrell Jul 24 2006, 6:19pm says:


I just completed it, and the mod wasn?t... that great. Maaany things that could be better, but beacuse it?s only one person who have done this mod, it?s pretty good. It took me 1 hour and like 10 minutes to complete it on hard, and i?m a veteran to HL

The mod was hard, even if I usally thinks it?s more fun, but really, it was too hard on some places.
But the story were pretty good, I especially like the time warp, and the ending were nice, but only for those who like to play it again can see all endings.
But, more decorations would suit some places better, the enemies spawn places and etc.

I don?t mean to be negative, but I can?t be so positive like alfaalex101.

Good work, I think you can make some great mods in the future

+1 vote     reply to comment
NativeOne Aug 29 2006, 12:58am says:

That was my Sentiment as well...


incase the image thingy here don't work, here's the link..

+1 vote     reply to comment
djsaskdja Jul 6 2006, 5:00pm says:

I thought it was fun and the story was really good but it's a lot harder than half-life 2. The strider part in the graveyard and the last battle with the gun ships took me forever and many deaths before I finally beat them and the loading times were really long.

+1 vote     reply to comment
alfaalex101 Jul 3 2006, 12:25am says:

Before you can judge other mods fairly you got to see how hard it is to make a mod that is actually fun. You have to put passion, time and creativity to make something great. A room might take 2 hours to design and will take the player 15 seconds to get past it. I was so surprised this mod was done by 1 person!

+1 vote     reply to comment
OnboardError Creator
OnboardError Jun 30 2006, 11:14pm says:

Just think... one person... arent those mods made by teams?

+1 vote   reply to comment
Gem Jun 30 2006, 7:47pm says:

Well i liked the story and the idea, but... and yes there is a but, after trying mods like ShantyTown and Weekday Warrior, the mod felt like "its seen before". Dont take me wrong great scripting, and so but not a 10/10 more like 8/10... That was just what i thought about it.

+1 vote     reply to comment
OnboardError Creator
OnboardError Jun 30 2006, 1:46pm says:

Comments like yours make all the work that went into this totally worth it... Thanks!

+1 vote   reply to comment
Gem Jun 29 2006, 4:01pm says:

I think im gonna try this mod only because of alfaalex101

+1 vote     reply to comment
alfaalex101 Jun 29 2006, 10:21am says:

Oh My God! This mod gave me almost the same if not better experiances that I loved from Half Life 2! By far the greatest mod I have played for HL2. The Level design is superb and the ending is very very shocking. I would die to give this mod a 13/10. Just beat it 3 minutes ago and the ending still makes me want to go " Holy **** you ******* BITCH!". The ending all makes sense and leaves an impression on you. Gameplay is nothing short of keeping you on the edge. Want to re-live Half-Life 2 again with a different twist? Download this mod NOW! Even though it is mostly just new levels and no guns it dosent effect the mod at all. I am keeping this mod and going to share it with all my buddies. Oh and the storyline is one of a kind. Thank you so much OnboardError!

+1 vote     reply to comment
ZitaX May 25 2006, 7:30pm says:

Great mod!! I really enyojed the multiple endings! :D

+1 vote     reply to comment
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Released May 7, 2007
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Causality Effect
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