After hatching from an egg on Other's Island, a serpent spends time in the ocean, feeding and gaining strength. In early summer, they are prompted to swim up the Rain Wild River by both their own ancient memories and the prompting of special memory-keeper serpents, who hold more knowledge about their history. Once they reach a suitable cocooning ground, the serpents construct cocoons for themselves out of memory-stone sand and their own saliva, forming a case which contains their memories and essences. The case is eaten to regain those memories when a dragon emerges from it.
Serpents display a variety of colors, including blue, green, and white. Some serpents display eye-spots along the length of their sides.
Serpents are venomous, but their venom is not as powerful as that of a dragon. A spray of serpent venom will corrode wood, eat through cloth, and create severe burns on human skin; in comparison, a single drop of dragon venom is capable of killing a full-grown man.