Allow Teams
Checking this box allows players to team up and fight cooperatively against other teams or another player, rather than pitting each player against all the rest.
Show Enemy on Map
When this is turned on, enemy units will appear on the map as usual. If its turned off, youre flying blind.
Maximum Number of Teams
If this box is checked, you can set a limit of how many teams are allowed.
Plugins
If you have any additional maps for Myth II, you can simply drop them in your plugins folder (inside your Myth II directory) and they will show up in your map list.
If you have additional plugins (new units, physics, etc.) you can load them from the Plugins dialog; clicking the Plugins button on the right will bring up this dialogs. The window on the left displays all available plugins and the window on the right displays only active plugins. To make a plugin active select it in the window on the left and click the right arrow. To make one inactive select it on the right and click the left arrow. When you've organized your plugins click OK and your new plugin set will become active.