Whereas the purebloods are the spies of the yuan-ti, the halfbloods are the warriors, descending on human cities when the purebloods have sufficiently weakened their defenses. They resemble a roughly even mix of human and snake, most commonly appearing as snake-headed humanoids covered in scales (making them easily mistaken for true serpentfolk), though numerous variations on the theme exist (see below).
Halfbloods are bred for combat: their humanoid form, venomous bite, and relatively fast gestation and aging make them ideal foot soldiers. They are no simple grunts, however - besides their formidable psychic powers, the average halfblood is a genius by human standards, and many are brilliant strategists.
In addition to serving as warriors, halfbloods also make up the bulk of yuan-ti priesthoods, gathering in large cults beneath their abomination masters. Halfbloods are cruel and ambitious, and many feel powerful envy towards both the weaker purebloods (who get to enjoy lives of luxury in human society) and the stronger abominations (their leaders).
Cursed by a dark god, forge spurned are undead dwarves who toil for eternity at the whims of their master.
A forge spurned resembles the dwarf it was in life, but significantly larger, wrapped in barbed chains whose hooks dig into its charred flesh. The chains binding its form smolder with heat and in many places are half-melted into the creature’s body. In place of a beard, a cloud of ash and smoke constantly obscures its lower face. A forge spurned stinks of molten steel, burned hair, and charred flesh.
Forge spurned are created by Droskar the Dark Smith, the dwarven god of slavery, toil, and deceit. When one of Droskar’s followers dies, their souls are judged by the Master of the Dark Furnace, and those who are found wanting are pierced with burning barbs and sent back to the Material Plane as undead terrors to do Droskar’s bidding until they have paid their dues in the blood of his enemies. Each forge spurned must fashion a chain from the souls of their victims, and only when they have forged a number of links commanded by Droskar–as few as ten or as many as fifty or more–does the Dark Smith grant them reprieve from their torment with the gift of oblivion.
As the Master of the Dark Furnace is worshiped primarily by the duergar, the vast majority of forge spurned were gray dwarves in life, and lurk in subterranean lairs near magma vents or lakes of lava where the heat of their environs facilitate their smithwork. Other duergar revere them, but give them wide berth lest they become the forge spurned’s victims. A few renegade surface dwarves have turned to Droskar’s worship as well, and those who become forged spurned haunt dwarven ruins, especially desecrated temples of the other dwarven gods.
The most inhuman of all foulspawn, dolgrues were mutated from bugbear stock and twisted to be almost unrecognizable. Their bodies are so warped from what nature intended that they are in constant pain and agony that can only be relieved for mere moments by inflicting it on their victims. Due to their insane, unpredictable behavior, even other foulspawn avoid dolgrues unless ordered to work with them by daelkyr.
Bar-lguras, or ape demons, are savage simian demons who haunt Abyssal jungles as ambush predators or serve demonic armies as scouts and skirmishers. They embody the danger of unknown places and the fear of being lost forever in the wild.
At first glance a bar-lgura appears like a hulking orangutan, its fur caked with filth, but its rheumy eyes burn with cruelty and savage intellect. Tusks too big for its head fill its fanged maw, and it has six digits on each vise-like hand and prehensile foot. They often wear jewelry and magic trinkets taken from their victims. Bar-lguras stand a head shorter than a human, but have far greater mass. They instinctively change the color of their fur to match their environment; when at rest they are rust-red or slate grey, and when enraged their fur turns a brilliant fiery orange.
Left to their own devices, bar-lguras come together in small packs led by the strongest male and stake out a patch of jungle, waiting for victims to catch, torture, and devour. Such wild ape demons erect gruesome fetishes around their territory made from sharpened branches and the body parts of lesser demons.
Bar-lguras are also favored as scouts and guerrillas by demonic armies. Angazhan the Ravener King, demon lord of apes, counts millions of bar-lguras as his subjects; many of Angazhan’s bar-lguras seethe with jealousy at his favored creations, the proto-demons known as baregaras. Angazhan also lends thousands of bar-lguras to his ally Demogorgon, the Prince of Demons, who appreciates the ape demons’ savagery. On the Material Plane, bar-lguras often haunt the jungles around shrines or temples to these two demon lords.