Boyon are small, mucousy, amorphous organisms indigenous to the planet Zebes. They naturally can be found at rest in the bottoms of small holes, but when something gets too close to their burrows, they suddenly begin leaping straight out of it repeatedly, presumably in an attempt to frighten away potential predators or accident-prone monstrosities that may step in their burrow and kill them. While no study has ever been done as far as anyone is knowledgeable of (although the existence of a Space Pirate base on the planet likely indicated that they would have performed some study of the creatures in an attempt to create new bio-organic weaponry), it could be presumed that they somehow use their amorphous structure to sense vibrations through the ground to indicate an approaching object; if this is the case, then they likely can tell the difference between predator and prey, assuming that they in fact are a form of predator.
It should be noted that they have more than a passing resemblance to the far more dangerous X Parasites, although this would appear to be simply coincidence. X Parasites are in fact translucent, which Boyons are not, and Boyons are not known to include a glowing nuclei at their center. However, if the X turn out through study to be genetically manipulated organisms, one might assume that a species similar to the Boyons were their origin, although Boyons being the parent species is unlikely, as the Chozo controlled Zebes until after the original X threat began, and thus it would be not tremendously possible for the Space Pirates to have created them from these creatures.
- Super Metroid (First appearance)