Cuthbern I is a hot planet with no atmosphere and is the closest of the two planets to the Cuthbern sun. Its lifeless, rocky surface holds a memory of a great volcanic past. The planet had once been covered in oceans of fire, though eventually these cooled and hardened into slabs of rock.

Even after the planet's core became less volatile, frequent eruptions continued to change its landscape. In addition, there is evidence of at least six asteroid strikes, large enough to have left epic craters on the surface of the planet which is left defenseless by the lack of atmosphere. There are still several active volcanoes left on Cuthbern I, mostly in the southern hemisphere. However, for the most part, the once burning terrain has been transformed into deserts of sand, as the planet's dry winds have eroded the rocky remains.