Mondreus is a planet given as the origin of the Bounty Hunter Spire, the last known Diamont. Its status is unknown, and depending on what circumstances led to the Diamonts' disappearance, it may no longer exist. Regardless of the case, Samus Aran is never seen setting foot on this planet.
The introduction cutscene of Metroid Prime Hunters shows Spire in a location that may represent Mondreus, as a barren and rocky world with an orange sky, not unlike the appearance of the Diamonts themselves.
| Planets in the Metroid series |
|---|
| FS-176 |
| Bilium | Oormine II | Tallon IV | Twin Tabula | Zebes |
| Alimbic Cluster |
| Alinos | Arcterra |
| Dasha region |
| Aether | Dark Aether |
| Federation Solar System |
| Bryyo | Elysia | Norion |
| Unknown Solar System |
| Pirate Homeworld
a.k.a. Planet SN-883 or Urtraghus ("large booty") |
| Small star |
| Phaaze |
| SR388's solar system |
| SR388 | "SR387" |
| Sun |
| Earth | Jupiter |
| Bermuda System |
| Excelcion | Talvania | Bion |
| Extreme Galaxy |
| Outlaw | Maru | Agricultural world | Jatsuk | Ocean world Graveyard planet | Galactic ruins |
| Other Locations |
| 2466 URSA | Bes III | Devon III | Daiban | Demon Planet | Degrade Jamoru | Jasdam | Jigrad | K-2L | Kankei | Liberty Mondreus | Naishii | Nest | RX 338 | Solairon 12 | Tivus | Vho | ZDR |