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How to Set Up Multiplayer via IPX on Civilization: Call to Power and Call to Power II
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call-to-power-multiplayer-instructions.md

This is a guide for how to set up Call to Power multiplayer (with Civilization: Call to Power or Call to Power II) by using ZeroTier One, IPX Wrapper and (optionally) mods. It focuses on Windows, specifically.

This guide will focus on joining an existing ZeroTier One session. For information on how to set up a ZeroTier One session for others to play on (IE, to host matches), please see this Gist: https://gist.github.com/justinfarrelldev/6f4a2d4e1ab971278ccb520d2376c41a

There is also a video version of this guide here: https://www.youtube.com/watch?v=WuDarvkafzo

Multiplayer?? How???

This method works by turning IPX packets into UDP ones via IPX Wrapper. Once these packets are converted, they can be used for LAN games again - then, we can share our connection using ZeroTier One with other computers over the internet.

A Couple of Quick Notes

You may not need IPX Wrapper if your operating system still supports IPX - that is, you are running a Windows machine that is older than Windows Vista. In that case, you can safely ignore all instructions regarding IPX Wrapper throughout the rest of this guide.

Additionally, you will see another option for connecting via LAN - TCP/IP. Unfortunately, this method of connecting does not seem to allow players to see each others' lobbies when connecting, meaning that players will not be able to join each others' games. It is for this reason that IPX was chosen as the method to use.

Requirements

To join an existing multiplayer lobby using this method, you need:

  • The ZeroTier 16-digit Network ID of the session you want to join
  • The release ZIP file (NOT the one ending in '-src.zip') from IPX Wrapper (linked in the Steps section)
  • An installation of the Call to Power game that you wish to join

Steps

If you are joining a modded, non-vanilla game, please skip to the bottom of this guide and read that first (then come back here once you've done that).

Here are the steps to follow to join an existing lobby:

  • Download ZeroTier One by clicking the appropriate download link on that page
  • Install ZeroTier One on your system
  • Once installed, type "ZeroTier" into your Start Menu and run the ZeroTier app. You will not see any applications pop up - ZeroTier will instead be present in your system tray. I will explain how to access it later, for now let's move on to the next step
  • Download the release of IPX Wrapper (NOT the one ending in '-src.zip', the other .zip one) here. This will also be in the Call to Power Discord's Mods and Resources channels
  • Unzip the ZIP file for IPX Wrapper that you downloaded by right clicking it and choosing "Extract All" and clicking "Extract"
  • Open the folder that you unzipped and copy all of the files (wsock32.dll, ipxconfig.exe, etc) into the Call to Power installation that you wish to use to join the lobby. You can use Steam to find this folder if you have installed it that way (click on Call to Power II in your library, click on the settings gear, click browse and then click on "Browse local files"). You should get a message asking if you want to replace license.txt, which you can effectively skip
    • You should paste the files next to ctp.exe or ctp2.exe (these are found in ctp_program\ctp or ctp2_program\ctp, respectively)
  • If you are on a 64-bit version of Windows, run directplay-win64.reg, otherwise run directplay-win32.reg
    • When in doubt, try directplay-win64.reg and see if it works. If not, do the other one
    • You will see the following, click on "Yes":

image

  • Once you do that, you should see a similar message to the following (click "OK"):

image

  • IPX Wrapper is now set up and ready-to-use. Keep in mind that you may need to occasionally re-run those .reg files in my experience (in my case, after my computer restarts)
  • Now we just need to connect ourselves to the ZeroTier One session that the other person is hosting
    • ZeroTier will be in your system tray (usually in the bottom right of your screen) and is the yellow icon in the top-left of the tray in the image below:

image

  • Right-click on the ZeroTier icon and click "Join New Network"
  • Enter the 16-digit Network ID (it should have been given to you by the person hosting the game)
  • Once you enter it, you should now see a new network option (in the image, it is the "Call to Power" network):

image

  • Make sure you have actually connected to the network - if you are, you should see a checkmark next to the network and a similar interface to this:

image

  • Now, open up Call to Power, click on Multiplayer and choose IPX. Create your profile, and click "Next". You should see "Joining Lobby". You should now see the other available players within the same lobby (assuming they are joining at the same time as you are)
    • Sometimes it's a little bit finnicky. If the players don't show up, try disconnecting from the ZeroTier One session and re-connecting, then starting Call to Power again
  • Enjoy your game!

Modded Games

Some mods (such as the Super Apolyton Pack) allow you to play via IPX just like the base game. This is very fortunate for us, since we are able to take advantage of the above techniques to play games with each other on these classic mods!

Here are the first steps to set this up (do these before everything else in the "Steps" section above):

  • Install your mod
    • You can use the Call to Power Mod Manager to assist with the installation of many of the mods such as the Super Apolyton Pack v2.0 and the Lord of the Rings mod
    • Alternatively, you can use the tried-and-true ModSwap utility to swap between the mods (which is available in the Discord under Modding Tools, if you do not have it already)
    • Using either the Mod Manager or ModSwap is necessary as, while copy+pasting the mods does appear to work for some mods, these programs will switch between the gamefile.txt for you (which is extremely convenient)
  • Start the game to ensure that the mod was applied successfully
  • Once you are sure that the mod was applied successfully, follow the instructions in "Setup" and you should be good to go!
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