Use the following instructions:

1. Install the playdeb package.

2. Or configure the repository manually:

   Go to System-Administration-Software Sources, Third-Party Software tab, Add:

   deb http://archive.getdeb.net/ubuntu -getdeb games

   Add the repository GPG key, open a terminal window and type:

   wget -q -O- http://archive.getdeb.net/getdeb-archive.key | sudo apt-key add -

3. Click the "Install this now" button below the screenshot of the desired game.

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