Backdraft Bubblish Gum

is the Ignition Ability of Tōru Kishiri.

Usage
Tōru inserts some bubblegum in his mouth and chews it, blowing up a balloon with a vacuum inside it that contains flammable gas. The balloon is lighter than air and, as such, is able to float. When given a command, the balloon pops, causing the flammable gas to react with oxygen, which leads to an explosion.