In this video, I show you my new command, which adds a new difficulty to your world. This HELL mode will probably make your Minecraft experience rather problematic! :P
You can see a command has say Have fun you can edit by command block
Take a look https://www.youtube.com/watch?v=DoC1L_deUlk&index=1&list=PLyXAokTk6BI4KvBPxYQSwYAZIFqx8bFjG