Pythor challenges the other Serpentine Generals in the Slither Pit, winning their staffs and uniting the tribes under his command.
The Ninja hold a tournament to see whose weapon will glow, believing it will reveal who is destined to be the Green Ninja. [S1E8] The Snake King
If you are looking for a different series, "The Snake King" (or a very similar title) appears in these contexts: Pythor challenges the other Serpentine Generals in the
Lloyd Garmadon is taken prisoner by the Serpentine after attempting to spy on them. Other Possible Matches [S1E8] The Snake King