The Gremlins are the titular antagonists of the popular movie franchise of the same name, based very loosely on the mythological creatures said to vex aircraft these monsters were notable for being mischievous and chaotic, obsessed with destruction and cruel practical jokes. They are largely unknown reptilian goblin-like creatures.
The Gremlins also had a primitive social-structure with more cunning and vicious members gaining higher rank via bullying or outright murder - the most powerful of the Gremlins in the original film was the manipulative but deadly "Stripe".
In the second film, due to genetic-engineering, a number of other unique Gremlins were "born" - amongst them was the Brain Gremlin, who was stereotypically civilized yet also brutal in his methods: becoming a spokesman of sorts for his kind.
Although almost universally dangerous and corrupt, Gremlins actually have a fairly innocent beginning as the furry critters known as mogwai, when a mogwai becomes wet or is fed after midnight a Gremlin is born and their physiology and behavioral patterns alter dramatically.
Gremlins are also somewhat carnivorous, though in general Gremlins are not out to devour human flesh - they much prefer to raid human homes and stores for sweet foodstuff such as candy or cookies. Other foods they enjoy to eat are chicken legs, frozen yogurt, and a sandwich with ham, cheese, and lettuce.
Gremlins do love destruction though and will happily tear apart electrical equipment, hijack vehicles and ambush people - attacking them with their sharp teeth and claws.
The Gremlins main weakness is exposure to direct sunlight, which causes them to melt into puddles of goo and kills them in the process - for this reason both Gremlins and Mogwai are naturally scared of bright lights.
Multiple Gremlins are briefly seen in the crowd of Oasis civilians during the final battle.