My name is Peter. I'm a Linux-using quantitative analyst by day, and a video game enthusiast by night. If you find this guide useful, let me know. I like making new friends around the world. I live in NYC but enjoy meeting people from all around the world. I tend to play co-op FPS and RPGs. I'm a completionist and I like going slowly, collecting all achievements and Easter eggs. If you want to play with me, let me know!


There are two types of Sven Co-op players: the host and the players.

• The host must follow these instructions.
  
  
• The players should read these instructions, especially if they are located geographically far away from the host. Not following these instructions will cause the players to dynamically download each map from the host. Not so bad if you're in the same room as the host. Pretty bad if you guys are on different continents.

This guide was not meant to be skimmed: you should read the whole thing entirely. There are some gotchas playing Opposing Force and Blue Shift in Blue Shift, but it's possible to overcome almost all of them. The things that can't be overcome are listed in the last section on bugs / limitations.


I would like to thank my wife for being a good sport about playing these games despite not being the world's best jumper. Love you, sweetie. "Oh no, another jumping puzzle!" Haha! :-)

I'd also like to thank my good friend Takashi-san. I'm glad we bumped into each other -- I love playing games with you. We are both "completionists". Our playing style complements each other.

• Make sure you have Opposing Force purchased through Steam.
  
• Make sure you have Opposing Force installed in Steam.
  
• Launch Opposing Force and play it for a few seconds.

• Make sure you have Blue Shift purchased through Steam.
  
• Make sure you have Blue Shift installed through Steam.
  
• Launch Blue Shift and play it for a few seconds.

Some insist on asking dumb questions like "Do I need to purchase the game?" despite what I wrote above. Yes, you do need to have purchased the game. Not necessarily from Steam, but you do need to legally own the game. Do not pirate software.

Navigate to Steam\SteamApps\common\Sven Co-op\svencoop. You'll find two batch files:

• Install_OpFor_Support.bat
  
• Install_bshift_Support.bat

You will use them to extract the games to where Sven Coop can find them. Sadly, they don't work "out of the box" any longer, but we can fix them. The goal of step 3 is the fix these batch files and run them.

In the same folder as the two batch files (Steam\SteamApps\common\Sven Co-op\svencoop) you'll see a file named

• FindHLDirectory.bat

This batch file is responsible for helping our two installation batch files find the respective games. Unfortunately, it is broken. Open it up with your favorite text editor and change this line:


to this:


Save and quit.



In the folder Steam/steamapps/common/Half-Life/ you will find four folders named:

• gearbox
  
• gearbox_hd
  
• bshift
  
• bshift_hd

Copy these four game folders to Steam\SteamApps\sourcemods.



In theory, the two installation batch files are now fixed and ready to go. Return to folder Steam\SteamApps\common\Sven Co-op\svencoop and run the two batch files:

• Install_OpFor_Support.bat
  
• Install_bshift_Support.bat

If you see errors at this point, I can't help you. It worked for me. You'll also see the following messages:

"Use the "-sp_campaign_portal.bsp" map to play the Opposing Force single-player chapters in Sven Co-op."

Just letting you know, I didn't need to do this. Maybe it's stale information.

If your friends can't bypass your firewall, then you won't be able to play with them. The good news is that once you successfully complete this step, not only will Sven Co-op work in Co-op mode, but all co-op games based on Half-Life GoldSrc (e.g. "Cry of Fear") should also work in co-op mode. There are two possibilities:

1. * Your firewall is either weak or not running at all, in which case, go directly to section 5.
   
2. * You need to let your friends get through your firewall, in which case, go to the next step.

There are two ways to do this: a) use a virtual VPN application like Hamachi, or b) poke a hole in your firewall.


I know nothing about this. Supposedly Hamachi is very easy to use, but you're on your own since I only eat Hamachi; I've never used Hamachi. The downside is that everyone you play with will also have to install and run Hamachi (or whichever VPN you're running). Furthermore, you may run into trouble if there's more than one person on your LAN who wants to play Sven Co-op.


You must "port forward" the following ports:


Note: The method how to do this will vary from person to person. it depends on what modem / router / internet service you're using. It's impossible to cover the almost endless ways to do this on everyone's hardware. Being able to port forward on your modem or router is a very useful skill for gamers, not just for Sven Co-op. As mentioned earlier, completing this step will allow you to play many other games based on Half-Life GoldSrc in co-op mode (e.g. Cry of Fear).

The host must follow the instructions in this guide... it's mandatory. All the other players ought to follow these instructions, but it's not mandatory. Why?

Think about what we did. We made the game maps available to Sven Co-op. Anyone who doesn't follow these instructions won't have the Opposing Force / Blue Shift maps available, therefore, every time the map changes, Sven Co-op will download the map from the host to the player. This is why the host must follow these instructions and the players should follow them:

• The host will always have the maps.
  
• The other players will download the maps from the host when the maps are needed.

From experimentation:

• A person on my home LAN in the same room downloads the maps and is ready to play in about 10-20 seconds on a standard Gigabit ethernet connection.
  
  
• I'm in New York City. A friend in Tokyo has to wait about 2 minutes for a typical Opposing Force map to download before he can play. We both have high speed internet connections. One of the larger maps took 4 minutes.

So you see, it can be a pretty painful wait if you have far away players. Unfortunately, people can play immediately once they enter the game, so that means the host can start playing right away. If you want to be polite you just sit and wait, waiting for your friend to connect. There are maps that are so short that if you did start to play immediately while your friends are downloading maps, you can easily finish the map before they connect!

Moral to the story: Everyone should just buy a copy of Opposing Force and follow the instructions of this guide. It's better that way.



Each map "knows" what the next map should be, so you don't have to keep track of which map you're on and which to load next. That information is stored in the map's corresponding cfg file (you can also edit this file to change your starting ammo/weapon load-up). However, there is a big nota bene here.

There are two ways to serve a Sven Co-op game: Using the "listen server" and the "dedicated server". I'm not 100% sure of the difference, but I think it amounts to this:

• The "listen server" is a combined "server / client". You run the game, and within the game you create a server. If you run Sven Co-op and run "Start a new game", you're using a listen server.
  
  
• The dedicated server is different in that you start an external executable, named svends.exe, and THEN you run Sven Co-op (named svencoop.exe). When doing this, you have to search for your server on the list of internet servers, and you connect that way.

Why am I mentioning this in a guide on Opposing Force and Blue Shift in Sven Co-op? Because of map continuity. There are two places in Blue Shift where you return to a map you previously played. Specifically, this happens with maps ba_yard3 / ba_yard4, and ba_teleport2. With these maps, you need to perform an action in another map and then return to these maps. Once the action is performed, the scripting is different. Without the changed scripting, there's no way to proceed with the game.

For some reason, when you use the Listen Server, the game "forgets" that you've performed the action. For example, with ba_teleport2 the sequence goes:

teleport1 --> teleport2 -> power1 -> power2 (perform action) -> teleport2 -> outro

When the action in ba_power2 is performed, ba_teleport2 is scripted in such a way that allows you to proceed to ba_outro.

With the listen server, the game "forgets" you've performed the action, so it puts you into an infinite loop consisting of teleport1 -> teleport2 -> power1 -> power2 -> teleport2 -> power1 -> power2 -> teleport2 -> power1, etc.

After Googling this problem, I found that using the dedicated server fixed it. For whatever reason, when you run the game using the dedicated server, it remembers you performed the action and you can proceed with the game without falling into the infinite map loop.

TL;DR: Don't use the listen server. Use the dedicated server. (ref)


One last note. When I used the dedicated server, it ignored "Max. players". The server kept starting with max players = 2 regardless what I entered in the user interface.

To change max players to something else, add this:


to server.cfg. I had three files named server.cfg, so I added that line to all three and it worked. (ref)

It is with great regret that I inform you that the last boss, The Gene Worm, is completely bugged. He doesn't spawn in Sven Co-op.

This is a known issue. One of the devs said it would be fixed sometime in 2017, which is obviously overdue, so don't hold your breath. This means the last Opposing Force map is effectively of6a5. The game ends when Barney says "I got some weapons piled up here. You better take as much as you can carry, because I think this is it! Good luck, corporal!"




There is a serious bug in map ba_elevator. In this map you ride an elevator down to the lower level while the resonance cascade occurs in Materials Science. In short, the elevator gets stuck and the map cannot proceed. The only way to continue the game is to quit out of the map and load the next map, ba_canal1. Another possible solution is to use SV_CHEATS 2 and CL_NOCLIP 1 and float to the bottom of the elevator shaft.

This is a known issue. A dev claimed this bug is related to frame rates and will be addressed some time in 2017.