Over time when they were locked in the Stone Army Vault, the Serpentine adapted to it and made it their new home. Eventually, they managed to open the door, and some of them moved to Ninjago.
When the Nindroid crisis began, the ninja journeyed underground to find the Serpentine, seeking to know more about the Golden Master. Eventually, the ninja came across the village, and were confronted by Skales, who introduced them to their new life under the surface. Acidicus told the ninja of the curse of the Golden Master, before Cryptor arrived with the nindroids and attacked the Serpentine. The ninja protected their former adversaries, shutting down most of the nindroids. When they asked the Serpentine to help them in their quest, Skales told them they wished to stay out of the conflict. However, when the Overlord became the Golden Master, several of the Serpentine left the tomb and helped the people of Ninjago escape the ensuing war in the city.
After The Titanium Ninja
After a short search for the Serpentine, Pythor found the Serpentine village, where he met his long-lost friend Skales. The Snake King didn't want to let him into the village, but Pythor finally convinced him. He tried to show Serpentine that he was still worthy of being one of them, because he was the first to show them the Thermodynamic Temperature Gauge from the BorgWatch. When Skales Jr. began to believe Pythor, the ninja invaded the village and forced Pythor to escape.
When the ninja needed Skales' help with Aspheera, they found him in the sewers in the Serpentine village. Skales then took them to the Serpentine library, where Acidicus explained to them everything they needed to know.
Shortly before Wojira flooded Ninjago City, the Serpentine left their village and came to the surface at the behest of the Police Commissioner. Later, the village was flooded with water, but after the defeat of Wojira, Nya returned the water to the sea.
- 108. "Ancient History"
- The reason why the Serpentine formed a new village and did not return to Ouroboros is probably that in the time shortly before the Nindroid crisis, the Lost City was used by the nindroids as a base.