The Bubble Gun is a bonus weapon in Resident Evil: Revelations 2.
The Bubble Gun is made available for purchase in the Rewards menu after completing all of the episodes in Countdown Mode. It is listed under the name "Bonus Weapon: Lil' Something Special Just for Natalia" before unlocking and later "Bonus Weapon: Bubble Gun" for 50000 BP. It can be equipped from the workbenches in Barry's campaign and does not take up any weapon slots. Like all bonus weapons, the player will only get a C rank for the chapter if used.
When equipped, Natalia will aim the Bubble Gun instead of pointing. She can then utilize the toy gun to shoot bubbles at enemies which will trap them for a short period of time. This makes it easier for Barry and Natalia to fight or escape oncoming enemies. Only one enemy can be trapped inside a bubble at a time.