Enclave Hellfire troopers are easily identifiable by their unique namesake power armor and signature flamethrower weapons. Often encountered starting at mid to high levels, Hellfire troopers are often paired with 2-3 standard Enclave troopers and occasionally even an Enclave officer, whether on patrol, stationed at an Enclave outpost, or inserted into the field via randomized Vertibird drop-off points. They are tough, and highly persistent combatants who will not let up for a second in a fight, relentlessly firing their weapon at anyone unlucky enough to come into contact with these fearsome soldiers.
Their heavy armor, combined with their significantly higher-than-average health (which is on par with most companions), allows them to survive noticeably more damage than any other humanoid combatant, with the exception of certain special characters (such as General Jingwei).
The Broken Steel add-on also adds a new rank of standard Enclave soldier wearing Enclave Hellfire armor and equipped with plasma rifles. These new Enclave soldiers have the same stats as Enclave Hellfire troopers, but are labeled as "Enclave soldier" rather than "Enclave Hellfire trooper".
They bear the Hellfire title only when using their signature heavy incinerator, though the ones armed with plasma rifles are still a large threat.
Sometimes they will appear before the player has started Broken Steel if the player has it loaded, if the player reached certain amount of level.