Stone Dragons have a tough outer covering made of a stone-like material. They eat rocks, using the minerals they contain for nourishment and to keep up their stone outer shell. They rarely move, and are the heaviest of all types of dragons. Although they have wings, indicating flight ability, no one has ever seen a stone dragon flying.

Dragons are highly-intelligent reptilian creatures that—from a human perspective, at least—appear to live forever. Many different varieties of dragon exist, each with their own unique qualities, habitats, and behavior. Adolescence in dragons is usually marked by the growth of a hatchling’s wings, although not all breeds of dragons grow wings and some breeds have other traits that indicate the beginning of maturation. In Galsreim, dragons and humans coexist peacefully.

Stone Arc really is a rock. He's rough, tough, and ready to fight. Unlike Mani, he puts his pride aside and does what's right, even if ohters don't agree. His decisions are almost always set in stone. Muy Pequino looks up to him, though he is younger than she. He protects her, and she gives him gems she finds when she's out scavanging. Although he seems like a goliath, he has a soft side.

At night he has his own place where he goes to think: a crystaline cave that's near the sea. He usually goes there at night, when he can concentrate, and he knows Pequi is safe. He's rather dumb, but he sometimes thinks really profound thoughts that impresses all of Belle's dragons.