Note: In 2023, Ninjago was rebooted as "Ninjago: Dragons Rising" (new characters, new timeline). So Season 15 remains the true end of the "Masters of Spinjitzu" era.
: Compare fan theories that existed before the season aired (like the identity of the Crystal King) with what actually happened in the "complete" story. legoninjagomastersofspinjitzus15complete best