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Varos is tidally heated by the gravity of Bretheda, which distorts Varos' shape as the moon revolves around the planet. Because of this, Varos' surface is almost completely covered in volcanoes and magma rivers, which constantly shift and occasionally rip open portals to the Plane of Fire. Several types of gemstones can only be found in the turbulent mantle of Varos and nowhere else.1
Varos' atmosphere means only heat-hardened creatures can dwell safely on the moon. The most notable of Varos' natives are fire-worms which swim in the lava moving from volcano to volcano. Visitors include various elementals and spellcasters who seek to harness the raw elemental power, the portals to the Plane of Fire, the various summonable predators, or the unique gemstones.1