"...Juice!" - The Bat gremlin about to drink the serum
The Bat Gremlin was one of the many gremlins that invaded the Clamp Center building. This gremlin drank from a bat serum in the Splice O' Life laboratory and quickly transformed into a bat/gremlin hybrid. As a result of the serum, it grew wings, its front arms shrunk as well as the ears (they also curved inward), and the eyes became beady.
The gremlin drank an animal bat DNA serum in the laboratory mistaking it for juice and transformed into a bat-like gremlin creature, whereupon the also recent mutated Brain Gremlin injects him with genetic sunblock and sends him out flying to see if the sun is still out and to wreck some havoc.
Later, the Bat Gremlin sits on a cathedral and gets in a conflict with Murray Futterman who is on the street below with his wife. Futterman fights the Bat Gremlin a bit, getting clawed at one point, and finally manages to get a hold of the creature's feet and shoves it down onto some wet cement before pouring some more cement on the creature. Despite being drenched with wet cement, the Bat Gremlin manages to get up and flies away, landing on a small tower on the cathedral's roof, where the cement finally hardens and practically turns him into a stone gargoyle where it wood stand for all eternity.
- When the Bat Gremlin crashes out through a window in the laboratory at Clamp Centre, the broken window looks exactly like the Bat-symbol as seen in the Batman universe.
- He appears as a common enemy in Gremlins 2: The New Batch (video game) in the NES version, where he spins himself to make several tornadoes, forcing the player (Gizmo) to attack the Bat Gremlin far away from it. In the Game Boy version, the Bat Gremlin is a boss.
- Even though the Brain Gremlin is the leader of all gremlins, the Bat Gremlin is the only one who the Brain gave a command to, which makes the Bat Gremlin the only known henchman of Brain, although there were probably others not seen in the film.
- The Bat Gremlin must be a reincarnation of one of the gremlins who ran Murray Futterman's house over since the Bat Gremlin wouldn't have attacked him unless the gremlin recognized him.
- In Japan, a bat gremlin figure was released.
- The scene when the Bat Gremlin begins to fly was created using miniature puppets.