cube2 software package provides 3D first-person shooter game engine, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install cube2
cube2 is installed in your system.
Make ensure the cube2 package were installed using the commands given below,
$ sudo dpkg-query -l | grep cube2 *
You will get with cube2 package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Games |
| Package | cube2 |
| Version | 0.0.20130203+dfsg-2 |
| Description | 3D first-person shooter game engine |
| Sub Section | Games |