The Electric Gremlin, also known as the Lightning Gremlin, was a mutant gremlin that appeared in Gremlins 2: the New Batch.
Originally just a normal Gremlin, he drank an Electric serum of raw energy which was originally tested on mice in small doses to power lightbulbs, but because the gremlin drank the entire vial it transformed him into a living lightning bolt of raw power.
Later when Dr. Catheter and Billy are in the lab hunting for weapons, the Electric Gremlin appears out of an electric socket and electrocutes the "good" doctor before disappearing back into the electric socket.
Later when Billy goes to speak with Daniel Clamp, the Electric Gremlin pops out a wall socket and tries to kill them. Billy manages to trap it in the phone, where it realizes its trapped he starts to scream.
Later, in the climax of the film, Billy grabs a nearby phone and releases the Electric Gremlin on the unsuspecting gremlins who had been doused in water, electrocuting them all, minus Greta. The Electric Gremlin probably short circuited, causing it to die.