From Destinypedia, the Destiny wiki
Unstable Incendiors are tougher to take on than regular Incendiors. Their superior armor and Solar absorption shielding grants them more durability, therefore giving them more chances to incinerate Guardians. Their Cabal Magma Launchers are versatile weapons in combat. At a distance, they fire jets of flames that leave a pool of fire upon contact with any surface. These jets inflict a damage-over-time effect that effectively strip the player's health in a matter of seconds. When faced up close, they are capable of launching a compression blast that pushes Guardians away from them and forcefully sends them flying into deadly obstacles in their path. Their fuel tanks can be shot, causing a massive explosion that can take out any other nearby Cabal units, but beware when fighting in close range because this explosion is also capable of dealing serious damage to nearby Guardians, and can instantly kill them within the proper proximity. Therefore, long-range energy weapons should be the best way to take apart their shielding and armor.
When Killed, Unstable Incendiors will drop volatile fuel cells used to detonate and destroy power arrays. If an Unstable Incendior is killed, but its bomb is used without destroying the array, an Unstable Warbeast will be summoned.
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