Synergy is a Half-Life 2 co-opertive multiplayer modification.

We have evolved from multiple mods (DC Co-op 2, Dev Co-op and Tim-Coop). This modification strives to give Half-Life players a true Half-Life 2 cooperative experience.

The mod features our own levels and the ability to play the Half-Life 2, Episode One and Episode Two campaigns cooperatively.

In addition, you can add more content by installing third-party mods, such as ROCK 24 and MINERVA: Metastasis, then playing them in Synergy!

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Hello everyone, it's been a while!I have some good news! We have some new development team members to introduce you to. Please officially welcome Travis (Krazy Kasrkin), Edfake and Patrick! They will be working on the various things with Synergy, including the code and maps.
What this means for you is: more updates and more development.We have a changelog ready for you all, which you can see here: Change Log - 44.We do have 2 screenshots to show you as well. We've added another vehicle type, which Fury_161 has created based on the original Buggy. Edfake has updated the scoreboard, with more changes planned. We're looking at figuring out a scoring system as well. Anyway, take a look below:

Also, we've finally returned some of the favourite Synergy content from before the 'OrangeBox' version! Please welcome back kilgore's maps, the Gargantua, the Combine Pulse Rifle and the MP5K weapons!
The following maps have been put back where they belong: syn_Apprehension, syn_DeadSimple, syn_FogIsland and syn_Forgotten_EvilsWe have some interesting things planned for next year, so stay tuned!
Happy Holidays from the entire Synergy Team!

If you do not have Synergy installed on Steam, you can do this by clicking on the following link: Run

Have fun!

Synergy Version 28 Live

Synergy Version 28 Live

4 years ago News 2 comments Report

Another update for Synergy! New characters for Donors and many bug fixes!

The FINALLY!!1 Update

The FINALLY!!1 Update

4 years ago News 16 comments Report

Finally! Actual UPDATE to Synergy, the cooperative mod for Half-Life 2!

Oh, yeah! remember that mod?

Oh, yeah! remember that mod?

4 years ago News 11 comments Report

Yeah, We are back. This time its actually working out between team members and everything is looking up.

"Still Alive..."

"Still Alive..."

5 years ago News 17 comments Report

A small update released that includes an updated map.

Post comment Comments  (60 - 70 of 418)
Colek Mar 26 2011 says: 0 votes     reply to comment
JonnyQuattro Aug 10 2011 replied:

Ok fine we'll put it back just because you said so.

+2 votes     reply to comment
kalidrone Dec 18 2010 says:

It would be SO ******* KICK-*** to play through HL2 and Episodes 1 & 2 Cooperatively, freakin' seriously! I anxiously await this! ^_^

+2 votes     reply to comment
Technodude010 Aug 10 2011 replied:

Dude what do you await? It's out for more than 2 years i guess. Just go to steam store and search synergy!

+2 votes     reply to comment
nadeboy Nov 29 2010 says:

Is this mod still being developed? Back in the day it used to be uber awesome.

+4 votes     reply to comment
Petrick Nov 26 2010 says:

Synergy needs more mappers.

+5 votes     reply to comment
MxN22 Oct 3 2010 says:


+2 votes     reply to comment
Santi95.95 Aug 19 2010 says:

i downloaded beta 2.5 and how do i play hl2 ep 2 campaing

+2 votes     reply to comment
aaroninbmore Aug 8 2010 says:

its on steam if this is dead. play with me on steam. if you want it free, download the synergy tool's and ta-da!

+2 votes     reply to comment
Stoudemire15 Jun 23 2010 says:

This look very promising I ma bored to death always wondering internet for fun and watching video I am tracking this modification.

I got one question does this project multiplayer support Coastline to Atmosphere and Strider Mountain cause every time when I play those game always give me headache and is ******* challenging as well.

+2 votes     reply to comment
Colossal Apr 25 2010 says:

What's the song in the start-up video?

+3 votes     reply to comment
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Release Date
Released 2007
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399 votes submitted.

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Highest Rated (4 agree) 7/10

Synergy was once the best Coop mod out there. Before it went to steamworks.

Before it went to steamworks it had awesome maps, badass new guns, custom player models, lots of other things, but then they went to steamworks and it unfortunately got bad. They ripped everything off it and left the custom player models just to donators.

The only thing I still like in this game is the "Trials" pack of maps. Only good thing left in it.

Apr 10 2010 by xXMaNiAcXx

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Last Update
2 years ago
854 members