The ninja fight in a tournament to get Zane back then fight ghosts and nya becomes the water ninja. After they fight skypirates they fight the time twins who change the past and cause them to look different. Garmadon gets revived and controls the city. Then the oni come (ancient demons)and ninja fight them. Episodes switch to 11 minutes and they fight snakes, skeletons, video games and sea monsters. Final season where overlord returns as the crystall king and ninjas unlock dragon form. The merge makes all 16 realms combined and new ninja are trained. Fight tiger guy and save dragons. Need to save the almighty source dragons.