**You must have custom server jar access for this. If you do not have custom server jar access, You can change it under "advanced settings" in your multicraft control panel.** It will not work without this access.
1. Stop your server
2. Create a folder on your desktop called server
3. Download the pixelmon mod to your desktop
4. Download the forge installer server (it is a jar file) to your desktop
5. Double click the jar file. This will create 2 jar files plus a directory called libraries
6. Rename the long jar file to custom.jar
7. Open your FTP client (like filezilla) and connect to your server
8. Using FTP, upload the two jar files and the libraries directory to the Main Directory
9. Using FTP, upload the pixelmon mod file to the mods folder. If you dont have a mods folder create one in your main server directory
10. Disconnect FTP
11. On the main multicraft control panel page, from the dropdown menu, choose "custom jar file use this"
12. Click save and restart your server