A Class XIII wasteland refers to the theorized ultimate result of Tallon IV's Leviathan impact, had Samus Aran not come to the planet. The planet's Logbook entry in Observatory stated that at its current rate of decay it would become barren after approximately 25 years. This class may also refer to the theorized ultimate result of Leviathan impacts on Aether, Bryyo, Elysia and the Pirate Homeworld, as well as the planetary class of Phaaze. Being that Elysia is a gas giant, the potential disaster might have had much more devastating effects than on other planets.
"Planet Tallon IV
Mass: 5.1 trillion teratons.
Profile: Ecosystem studies indicate that Tallon IV was a biological paradise prior to the impact of an extraterrestrial object. What remains of the biosphere is slowly fading due to exposure to Phazon radiation. At current rate of decay, Tallon IV will be a barren Class XIII wasteland in approximately 25 years."