ninjago season 2 ep 16 part 2 "The Temple of Darkness”

After collecting an artifact, Malachar and Vexor try to escape as the Temple of Darkness begins to collapse. A mysterious dark shadow emerges and leads them through a hidden passage to another chamber, where they discover a second artifact. Realizing the shadow has revealed another hidden treasure, they take the artifact and continue their quest to collect them all for Malachar’s plan.