King of Shadows

S1, E2: Long ago, four weapons of spinjitzu were created by a great warrior. When he passed, his sons were tasked with protecting them. However, the older brother, Lord Garmadon, wanted to use the weapons for his own powerful and evil intents. Sensei Wu was forced to banish his brother to the Underworld and hide the four weapons with dragons as guardians. However, Lord Garmadon has recruited an army of skeletons to find the map that will lead them to the four weapons. Sensei Wu needs Kai, Zane, Cole and Jay to use spinjitzu and the Tornado of Creation to find the weapons first. Only then will the world be safe.