- For the weapon designed by Cisco Ramon, which serves a similar purpose, see Cold gun.
The prison break
Caitlin Snow approached a seemingly panic-stricken Nora Fries while the latter frantically searched for something in a store room at Arkham Asylum. Caitlin asked Nora if she was alright, to which the latter responded that her procedure had been shut off, and that she needed to be cold. She then tried to hook up the freeze gun. Caitlin continued trying to talk to Nora to calm her down, but Nora said, "Get away from me," hitting her with a blast of frigid air from the weapon, prompting Caitlin to turn into Killer Frost. The two then started fighting, with Killer Frost calling out to her friends for backup. Immediately after this, Killer Frost was thrown backwards by another blast from the gun, rending Killer Frost unconscious, with her also turning back into Caitlin. As a result, when Oliver and Barry found her down on the floor, "Barry" (Oliver) attempted to throw a badly-aimed lightning-bolt at Nora, accidentally causing several vials of some sort of hallucinogenic drug to fall to the floor and shatter. These vials then released their contents into the air in a mist-like form, causing "Barry" (Oliver) to believe that "Oliver" (Barry) was Eobard Thawne, while "Oliver" (Barry) was made to believe that "Barry" (Oliver) was Malcolm Merlyn. As a result, the two began fighting, giving Nora time to flee.
- Sub-zero blast: The gun shoots and ejects a powerful blast of particles at presumably below 0°C, violent enough to blow Killer Frost across a room.