An incendiary grenade's casing has a fuze with a portion extending into the casing. Thermite disposed in the casing encases the portion of the fuze that extends into the grenade casing. Insulating material is disposed in the casing adjacent to the thermite. Layers of a titanium-boron intermetallic and an oxidizer are disposed in the casing. One layer of the titanium-boron intermetallic is adjacent to the layer of insulating material. This one layer of the titanium-boron intermetallic and a layer of the oxidizer adjacent thereto have a common-axis hole formed therethrough that is aligned with the portion of the fuze. A separating material is disposed at each interface between the titanium-boron intermetallic and the oxidizer.