The Fallen Ring Castle wasn't just a place where serpents could hide, they lived here. To do so, they needed resources - primarily energy, food, and water.
Serpents had no problem with energy and water. At the Red Zone of the Cave Grid, there was a high energy density even for very strong monsters. The serpents were fire monsters, so lava allowed them to quench their thirst. Well, hot springs were also an option.
But, to get food, one had to either gather or hunt.
The serpents had plenty of places to do that. After all, they had lived here much longer than Arnoth, and the Light Legion's terror lasted.
One of the best places was the blood pond.
Only the strongest of the serpents could go there. Not only because there were regenerative monsters at the blood pond, but also because the blood pond was lower than the Fallen Ring Castle.
Given the rules of the Cave Grid, this indicated that the average regenerative monster from the blood pond was stronger than the average serpent.
