The in-development multiplayer server for Death 3d is now online. In order to play online, you have to enable the loading of "unsafe" scripts in your web browser. To do this, go to the Death 3d game, and click on multiplayer. You will see the following icon come up. Click on it and choose Load Unsafe Scripts.
Don't worry about the "unsafe" part. It just means you are connecting to a non-HTTPS server from an HTTPS website.
You can find Death 3d on ApeWebApps here: www.apewebapps.com/death-3d/
The game is in the very early stages and the server may go up/down at any time. Enjoy.