What are some alternatives?
When comparing Punch Club and Unvanquished, you can also consider the following products
BotBoxer - A first ever robotic punching bag with computer vision
Quake - Quake is a series of first-person shooter video games released by id Software.
PunchLab - Track the strikes you throw at the punching bag
Unreal Tournament - Unreal is a series of first-person shooter video games developed by Epic Games.
ROBOCRAFT - Robocraft is an Action-Adventure, MMORPG, Vehicular-Combat, Shooter, Sci-Fi, Strategy, and PvP video game developed and published by Freejam.
Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.