Slimelord, the Monster Eel - S1.E13

After the little girl "Runlay" stole Sanzoh and effectively placed him before Slime Lord, Slime Lord would then make the preparations of boiling Sanzoh as a specific type of food -- an action that Dearth Voyd hopes will make Kongo ally with the Underworld. After Kongo enters in as a fly and attempts to cut Sanzoh's bonds loose, Slime Lord pursues Kongo with due persistence. After Kongo creates a fake Sanzoh with his hairs, Slime Lord becomes distracted, while Kongo then heads back to free the real Sanzoh. Soon enough however, Slime Lord would return in good time and duel it out with Kongo with his large cleaving sword. After some time passes and Kongo realizes that his hits have no effect on Slime Lord - his body is of rubbery slime like substance - Slime Lord suddenly unleashes his true form -- as a very large eel. Before Slime Lord has a chance to destroy Kongo in his true state, the young girl would transform herself into a dragon and duel it out with Slime Lord in defiance. After Kongo manages to retrieve her dragon stone, the young girl is able to defeat the Slime Lord with true ease. Following this point, Slime Lord would be seen as a small eel (small enough to fit in a small sack). Through Sanzoh's orders, Kongo frees the now rather small Slime Lord into a neighboring pond and then continues on their very long journey west.