Board Thread:Theories and Rumors/@comment-25015873-20141221222706/@comment-26577913-20150712170248

Pilot-Kai

Rise of the Snakes/S1-Kai

Rise of the First Spinjitzu Master/S2-Lloyd

Rebooted/S3-Zane

Tournament of Elements/S4-Kai and Garmadon

Possession/S5-Kai and Nya and Wu

Season 6/Pirate Season-Jay (because he has an eyepatch in the future)