Season 5: Possession

Story:

After Garmadon's sacrifice to stop Chen and the Anacondrai Cultists, Lloyd is faced with the loss of his father and depression. However, when he is possessed by Morro, former student of Sensei Wu and the Elemental Master of Wind, the Ninja must stop him from finding the Tomb of the First Spinjitzu Master and cursing the sixteen realms by releasing his master, the Preeminent, while learning a new fighting style, Airjitzu, along the way.

The Ninja become stronger as they find new friends, face their fears, and finding secrets that have been hidden. 

The Ninja face many new adventures as Lloyd is possessed. 

The uncover the three secrets of Airjitzu, retrieve the Sword of Sanctuary, and locate the first Spinjitzu's Master's tomb.

Sensei Wu reveals that Nya can have the control over the element of Water as her mother did.

 She joins the Ninja and unlocks her True Potential to save Ninjago from being destroyed by the Preeminent.

Episode:
45.''Winds of Change''
46.''Ghost Story''
47.''Stiix and Stones''
48.''The Temple on Haunted Hill''
49.''Peak-a-Boo''
50.''Kingdom Come''
51.''The Crooked Path''
52.''Grave Danger''
53.''Curseworld, Part 1'' (Season Finale Part 1 & 2)
54.''Curseworld, Part 2''