In general, A higgie will appear as a silvery entity, with black and/or colorful glowing features. Higgies always have little antenna on their head, 2 thick, clublike ones. Transparent pits on their bodies glow with a color specific to an individual. Orange and red are common colors, though most colors can be emitted by a higgie. Around a higgie will ussually orbit two things: a glowing energy ring, which doesn't have a clear purpose, and tiny satellites that a higgie uses for manipulation purposes. Higgies can easily change their shape, due to being so malleable. Their appearance is based on individual preference.
Higgies do not have a clear origin. They appear to be mechanical in nature, so one could surmise someone built them Higgies have a long history of traveling space in large groups, finding planets and engulfing them, eating them planet and anything on or in it.
Higgies enjoy either studying other entities, or trying to eat them. Higgies can eat anything. Living things, dead things, plants, meat, minerals, and planets, though the last one requires a whole colony of higgies working together. Any sentient race that encounters higgies and survives the encounter will likely be very afraid of them. However, survival is not likely, as a higgie colony is capable of devouring planets whole, all working together to drill and split the planet into tiny peices, leaving behind what can't be used as a much smaller, unrecognisable sphere of dross.
Higgies have tractor beam capabilities, used to move things around, usually closer or into themselves, if anything.