The 31-79 JGb215 (Often referred to as the "Shrink Ray" or "Baby Gun") is a wonder weapon only appearing in the Call of Duty: Black Ops map Shangri-La. The 31-79 JGb215 is a rifle wonder weapon, somewhat similar is size to the Wunderwaffe DG-2, which fires rays that shrink any zombies caught in the radius of the ray. The weapon does no damage, instead shrinking zombies, allowing them to be killed by anything in one shot, or by running into them. It holds 5 shots per clip, and holds 25 shots in reserve. In Shangri-La the 31-79 JGb215 can be acquired from the mystery box for 950 points. The weapon is required for the main easter egg quest, Time Travel Will Tell. Zombies affected by the weapon will grow back to full size after five seconds, except for the Shrieker Zombies and the Napalm Zombies, which revert after a much shorter time.
The origins of the wonder weapon are unknown. However, Dr. Edward Richtofen believes Dr. Ludvig Maxis invented the weapon.
When placed in the Pack-a-punch machine, the 31-79 JGb215 is upgraded to The Fractalizer. The magazine size is upgraded from 5 to 8, and up to 40 shots are held in reserve. The weapon still does no damage, however the zombies shrunken by the weapon stay small for longer, and the ammo is increased. The Fractalizer is also required for a part of the easter egg quest to be completed.
- The odd number based name of the 31-79 JGb215 is actually a set of coordinates, pointing to a location in the Himalayas.
- The Fractalizer's name is a reference to a Fractal, a pattern of varying size, referring to the shrinking abilities of the weapon.
- The dragon statue on the weapon is very similar to other statues found on the map.