The Ying-Yang World was a strange black and white dimension "where anything could happen" with its own laws of physics, completely different from the real world. It was the prison of Hannibal Roy Bean for over 1500 when Chase Young betrayed him.
The Ying-Yang World was a bizarre dimension with a crystal-like floor that was always covered with white mist and with a black "sky" with floating Chinese characters. Some other areas were filled on with snail stairs and even Chinese windows and Ying-Yang symbols gloating everywhere.
Effects on the Shen Gong Wu
Master Fung stated that the Shen Gong Wu can act different inside the Ying-Yang World. This was demonstrated when the Silver Manta Ray stopped working correctly and started falling in midair.
The Ying-Yang World had several known places like:
Hannibal Roy Bean's Prison
Hannibal's prison in the Ying-Yang World was a modern prison with vigilance towers and lights surrounded by a desert with a crystal tower in the middle where he was locked down.
When a person left the Ying-Yang World without the Ying Yo-Yo or the Yang Yo-Yo his good or bad chi would be left behind. Their Chi was stored in a stage similar to a supermarket store hall that appear at tough.
Inhabitants of the Ying-Yang World
The Chi Creature was a jet-black monster that was neither good or evil. It's only purpose was to keep the Chi from the Ying-Yang World safe. In order to do that, it sometime left the Ying-Yang World to recover the stolen Chi or even steal it from another person.
Hannibal Roy Bean
Hannibal Roy Bean was the most notorious inhabitant of the Ying-Yang World. After Chase Young turned evil, he betrayed Hannibal Roy Bean and locked him in a prison where he stayed for over 1500 years until the monks set him free.
THe Ying-Ying bird was the only known creature that could get in and out of the Ying-Yang World at will.