Theoretically, 12 classes of monsters can exist based on these separate characteristics.
Generated monsters are separated into classes of monsters based on three characteristics: The higher the threat is, the more powerful the monsters get. Monster attacks, physical features, and color are all assembled based on the seed of the planet, which allows coordinate sharing to include monster locations.
Many monsters that players encounter throughout the game are procedurally generated, meaning they are assembled 'randomly' from a characteristic set, like a planet.