The energy that GELLIN generates from photosynthesis is converted into electromagnetic pulses. It uses these as a means of propulsion.
Gellin's body is squishy and coated with a semi-permeable membrane. However, it has evolved six limbs for locomotion. It has horseshoe-shaped organelles on either side of its head, on each of its legs and on its tail. It also has large green mitochondriae on its forehead and back. Other than these, it lacks any sort of eyes, mouth or facial features.
Gellin uses the electricity it generates from solar power as a method of locomotion and self defense. Its special organelles can expel pulses of electromagnetic energy to move surprisingly fast as well as deliver a nasty shock.
Being rather simple organisms, Gellin are not particularly intelligent or empathetic, but they can follow orders decently well. They are big enough to ride, if you don't mind their squishy exterior, and are strong enough to run carrying a medium-sized human.