Pain Elemental

Pain Elementals are a species of floating demons with many similarities to Cacodemons, serving as living forges for Lost Souls, which damns them to an existence of constant pain.

Biology
Pain Elementals bear great resemblance to Cacodemons, who they are possibly related to. Like Cacodemons, they bear sphere-like bodies with a single eye, but unlike Cacodemons, Pain Elementals are brown-skinned, with an orange eye bearing a black pupil, two large, curving, black horns, sharp teeth, and two arms. What appears to be a more evolved breed of Pain Elementals has an armored backside, an overall slimmer frame, longer, larger arms with large claws, longer horns, an entirely orange eye, and several mandibles around their mouths. Pain Elementals serve as living "forges" for Lost Souls, taking the incorporeal essence of souls broken by intense slave labor into their bodies and turning the souls into physical manifestations of madness. The process is incredibly excruciating for the Pain Elementals, and repeats indefinitely throughout their lifespans, which are possibly finite. While their level of sapience is unknown, Pain Elementals are known to actively seek out targets to expel Lost Souls at to alleviate some pain from their bodies, and take great sadistic pleasure in the suffering of their victims. While all Pain Elemental breeds are capable of producing Lost Souls, the evolved breed appears to actually have some control over them, able to have them hover around them like a barrier. Unlike the original breed, which fires Lost Souls like a projectile, the evolved breed manually throws them at a target. Like Cacodemons, it is possible that they fly through a form of hot gas, evidenced by their literal flaming gut, as they explode if their eyes are ripped out or severely damaged. Unlike Cacodemons, Pain Elementals have red blood. The original breed of Pain Elementals appeared even more volatile than the evolved breed, and would leave behind some Lost Souls after exploding.

History
Pain Elementals rose from the deepest, darkest depths of Hell, known as the abhorrent creations of the Umbral Plains, and possibly related to Cacodemons or cyclopedic Titans. Pain Elementals forged Lost Souls within their very body, plunging them into endlessly excruciating pain, driving Pain Elementals to indiscriminately kill and torment those they saw as weaker than themselves. Pain Elementals were among the demonic forces that invaded Argent D'Nur, a world vassalized by extradimensional aliens known as Maykrs. The Night Sentinels, guardians of the energy-creating Elemental Wraiths and the military force of Argent D'Nur, fought against the demons, with the Deag Priests, a caste of Argenta priests serving the Maykrs, discovering Argent Energy- energy created by combining Hell Essence with Sentinel Energy. With Argent Energy now fueling their ranks, the Night Sentinels were able to push the demonic forces back, bolstered by an unnamed time-traveling Human man who joined their ranks, arriving just before the first wave of demons appeared. The man, first known as the Outlander, soon became the champion of the Night Sentinels, and was granted superhuman abilities by a Maykr Seraph named Samur. Now known as the Doom Slayer, the Human led the charge against Hell, but unbeknownst to the Slayer and the Night Sentinels, the Maykrs struck a deal with the Dark Lord of Hell, allowing Hell to conquer more worlds in exchange for Argent Energy, which allowed the Maykrs to remain immortal. The Doom Slayer and his companions were betrayed and locked away in Hell as Argent D'Nur fell, and in Hell, Pain Elementals and other demons launched an unrelenting assault on them. Only the Doom Slayer survived, and continued to fight the demons for eons, until he was locked away in a sarcophagus by powerful demonic priests, presumably including the very Deag Priests who had once served Argent D'Nur, now corrupted into Hell Priests. Pain Elementals roamed Hell until 2022, where they were used by the Icon of Sin, the most powerful of the Titans, to invade Earth after the death of the Spiderdemon known as the Spider Mastermind. While they quickly killed most of Earth's defense forces, they were unable to stop an unnamed Human marine, the same one who had killed the Spider Mastermind and stopped the initial invasion of Mars, who arrived on Earth and fought his way to the Hell portal the demons were pouring out of, destroying Pain Elementals who stood in his way. All surviving Pain Elementals were sealed in Hell after the Icon of Sin was killed. However, it appears that some Pain Elementals were used in the invasion of Mars, and were killed by UAC security forces before overwhelming the base, as the Mother of All Demons managed to get ahold of Pain Elemental corpses on the Martian moon of Phobos, reconstructing them into mutants with two mouths. Before they could be used to invade Earth again, the reconstructed Pain Elementals were found and destroyed by the same marine, along with the other reconstructed demons and the Mother of All Demons. After killing the Mother of All Demons, the marine voluntarily remained in Hell to ensure it could never again rise as a threat, somehow going back in time and across dimensions, becoming the very Doom Slayer that fought the demons for eons as the champion of Argent D'Nur. Pain Elementals gradually evolved to be somewhat slimmer, more armored, and grew larger arms and horns, along with mandibles around their mouths. The Slayer was eventually retrieved from Hell by Samur, now in the body of a Human cyborg named Samuel Hayden, and used to stop the resurrected Spider Mastermind from capturing Mars. After the Mastermind was killed, the Slayer was banished to the depths of space, although he returned in an Argenta space station, just in time to combat the Maykr-led invasion of Earth. After the Slayer killed two of the three Hell Priests, he went to Mars to chase down the last priest, Deag Grav, and Pain Elementals were brought out of Hell once more to attack the UAC Phobos outpost before the Slayer could utilize the BFG-10000. The Pain Elementals were unable to stop the Slayer, who blasted a hole into Mars to expose the lost city of Hebeth, dragged deep into the planet's surface, still holding an active slipgate that the Slayer utilized to reach and kill Deag Grav. Pain Elementals attacked the Slayer again as he retrieved his Crucible from Argent D'Nur and ventured to Urdak, but where destroyed. When the revived Icon of Sin broke the holy seal of Urdak, the demons betrayed the Maykrs and invaded, with Pain Elementals being present among them, but were unable to stop the Slayer from chasing the Icon to Earth, with more called out of Hell to the Icon's aid. After the Icon of Sin was killed once more, Pain Elementals remaining on Earth were gradually exterminated by a renewed Human resistance. Pain Elementals were also present in the demonic forces that attempted to stop the Slayer from retrieving the Life Sphere of Davoth, the first Dark Lord, but were cut down. At the Hell city of Immora, where Davoth fled to after being revived, Pain Elementals fought alongside Jekkadian Demonic Troopers against the Doom Slayer and his army of Night Sentinels that accompanied him to Hell, but were unable to stop the Slayer from breaching the walls of the city. Within the city, the Slayer utilized a Pain Elemental as a sort of slingshot to get him to Davoth, firing the chain of his Super Shotgun's meathook into the demon's hide. All Pain Elementals outside of Hell were destroyed when Davoth was killed.

Appearances

 * Doom II (1994)
 * Doom 64 (1997)
 * Doom Eternal (2021)
 * Doom Eternal: The Ancient Gods Part 1 (2020)
 * Doom Eternal: The Ancient Gods Part 2 (2021)