Games are everywhere and, with the sharp improvement of graphics in the later years, a new challenge is to create better interfaces to amplify the sensorial experience of game players. In this context, the present work proposes a desktop-based CAVE system using a variable number of displays with dynamic angles between them. Our hypothesis is that such a system provides an improvement in the players' peripheral vision for 3-D first person games. This would even benefit the player performance. In our implementation we used augmented reality and computer vision techniques to calibrate the monitors. Graphics libraries (ARToolK ARToolKit it and OpenGL) have been used to detect and calibrate monitors within the same 3-D space and calculate the angles between them. The open source game AssaultCube has been modified to support 12 monitors and different camera angles. The game is not only entertaining, but has been implemented as a use case for user tests, with a configuration of three monitors. Tests have shown the desktop CAVE system allows for performance improvement once the players make significantly less look-around movements with the mouse while keeping the average number of kills and deaths favorable in relation to a conventional one monitor setup.