Unnatural Meteos are Meteos that only appear in the Original Meteos when a match is started. They also don't always appear and as a result, Glow Meteos are the most common Unnatural Meteo. These are not to be confused with Hidden Meteos.
H2O: Megadom, Suburbion, Thirnova, Cavious
Soil: Grannest, Suburbion
Zap: Geolyte, Wuud
Zoo: Cavious, Wiral
Glow: Geolyte, Oleana, Boggob, Suburbion, Hevendor, Cavious
Dark: Firim, Anasaze, Gravitas, Hevendor, Gigagush