Incendiary gel is a highly flammable substance produced by the Covenant for use in Type-3 Antipersonnel/Antimatériel Incendiary grenades[1][2] and the assault cannons used by Mgalekgolo.[3]

The gel is actually a hazardous yet stable chemical compound which contains Cesium, a phosphoric alkali metal. When it comes in contact with oxygen the gel ignites and burns at 2200 °C (3992 °F). It is capable of causing horrific damage to both personnel and equipment, however the toxic nature of the substance renders any surviving flesh too poisonous for consumption.[1]


  1. 1.0 1.1 Halo: The Essential Visual Guide, page 68
  3. Halo: Contact Harvest, page 267