Yin Yang Yo! two rabbit twins named Yin (Stephanie Morgenstern) and Yang (Scott McCord) that train under Master Yo, a grumpy old panda who is eventually revealed to be their biological father. They learn the sacred art of Woo Foo, a special type of martial arts that involves both might and magic. They must work together to save the world from evil villains and forces that want to destroy, corrupt, or take it over. However, through all these adventures, Yin and Yang still portray stereotypical siblings; belligerently antagonistic but still ultimately caring about each other and working together when needed. During the first
Yin Yang Yo! season, the primary goal was to defeat the Night Master, a powerful enemy. During the second season, there are three primary storylines. The first one sees Yin and Yang trying to prevent other villains from being crowned the new Night Master. The second is Yang's own quest to find powerful mystic artifacts by some later-revealed-to-be villains: four evil heads who he thinks are the masters of Woo Foo. The third sees Yin and Yang against the original and reborn Night Master, Eradicus — ultimately trying to build a Woo Foo army to fight against his army. The setting is in