The Hell Guard is actually just a vessel for a parasite host that controls its host completely. These act as a powerful general among the armies of Hell itself and are judged to be the most difficult boss battle of the Doom reboot.

Tier: At least 8-C, likely far higher

Classification: Parasite Demon

Powers and Abilities: Immorality (Types 2,6 and 7; Demons are frequently referred to as mortally challenged and are referred to as an army of the undead), fire manipulation, large size (Up to Type 0), energy manipulation (Can create a wall of Argent energy), Superhuman physical characteristics, enhanced durability via natural armor, forcefield, reality warping (Passive. The demons with their presence bring their reality with them, "hellifying" the environment. This can lead to many destructive events, all of which benefit them on conquering worlds. Whether that be creating Hellgrowths or infecting  the atmosphere, making it poisonous), limited BFR (Whenever a demon kills, it gets sent to Hell), resistance to heat, poison, acid manipulation, fire manipulation, electricity manipulation, mind manipulation, disease manipulation, radiation manipulation, immunity to soul manipulation

Attack Potency: At least Building level, likely far higher (Far superior to the Baron of Hell and comparable to CyberDemon)

Speed: At least Supersonic+ (Easily comparable to Doomguy, more physically agile than the CyberDemon)

Lifting Strength: At least Class 5, likely higher (Should be comparable to the CyberDemon, is stronger than the Baron of Hell)

Striking Strength: At least Building level,  likely far higher (Should be superior to the Baron of Hell)

Durability: At least Building level, likely far higher (Capable of taking blasts from the BFG9000), higher with forcefields

Stamina: Infinite (The demons of Hell have limitless aggression and are tireless beings)

Range: At least Tens of Meters with ranged attacks

Standard Equipment: Powerful mace, magical staff

Intelligence: Unknown

Weakness: None notable

Notable Attacks and Techniques:

•Mace Leap: A Hell Guard with a mace will leap forward, smashing its foe.

•Fireball: Even more powerful than the Imp's, the Hell Guard uses its staff to launch a deadly fireball at its opponent.

•Flamethrower: A stream of fire used to incinerate the Hell Guard's opponents.

•Wave of Hell Energy: Shoots waves of raw Argent energy; can also create a short-range explosion like this.

•Fire Whirlwind: Spins to fire his flamethrowers and fireballs at a much higher rate, destroying most of its surroundings.

•Forcefield: A powerful energy shield which surrounds the Hell Guard whenever it's not attacking. The shield is powerful enough to absorb blasts from the BFG9000 without faltering.

Note: These beings seem to attack in pairs or groups.