LEGO Ninjago: Masters of Spinjitzu | S1E1 | Way of the Ninja

The four Ninja are snapped out of their post-hero complacency when Lord Garmadon’s young son Lloyd shows up and tries to pick up where his father left off. The Ninja dismiss him as a threat, but regret that choice after Lloyd wakes up the evil snake tribe. A prophecy is revealed that states a green ninja will ultimately defeat Lord Garmadon.