Howlers were 8 feet (2.4 meters) long, 8 feet (2.4 meters) tall, quadruped beasts that weighed about 1 ton (910 kilograms). They were patchwork creatures that seemed to cross traits of canines and felines, with bruised, crushed digits ending in claws on their front legs and back legs ending in hooves. Despite seeming gaunt, their backs were strong and resembled those of oxen. Their scales were covered by tangled, red fur that spread into a mane of trembling quills on the backs of their necks and surrounded their muzzled, simian faces.
Howlers were nonaggressive and usually cowardly when alone although extremely cruel when in packs. They practically stood when howling, and like dogs would do so for any number of reasons. They howled when lonely, trapped, frightened or challenged but despite their bestial behavior possessed a surprising level of intelligence, enough to understand language.
Young and inexperienced howlers killed their victims quickly for the delicious rush of terror that a violent death generated. However, older howlers preferred to draw long-term sustenance from constantly terrorizing their victims rather than killing them immediately.
Howlers rended the flesh of their prey and tore at the minds of the terrified with their wicked jaws. The quills on their neck became erect when they engaged in combat and formed a shield of spines when they charged. Their raised bristles, while inaccurate could break off and become lodged in their victims requiring each one of them to be carefully removed lest the victim suffer extreme pain.
Their titular howling was a horrifying sound that could be heard from a large distance, even through the loud winds of their home plane, and which caused other creatures to become debilitated by fear and incapable of complex thought. Prolonged exposure to their baying had a similar effect to the winds of Pandemonium, slowly driving the listeners insane and turning those nearby into stumbling wrecks.
The craven nature of the howler meant that they generally left large groups and seemingly dangerous beings alone, instead targeting the weak and vulnerable. Their cowardice was not to be confused with weakness, and when they decided to go on the offensive they did so with ruthless savagery and focus. The first few seconds of combat with a howler pack often decided the outcome of the entire engagement. After chasing and wearing them down they would descend upon their prey, primarily relying on their numbers, speed and paralyzing howling. They used hit and run tactics to gradually weaken their targets but fled if their attempts to single out weak prey stopped working.
Although they generally avoided civilized areas and tight locations, howlers on the Material Plane were known to terrorize isolated villages, feasting on the steady supply of flesh and fear generated by the inhabitants. Normally content to drag off one or two victims at a time, any display of defiance resulted in the pack surrounding the offenders home and devouring everyone inside after crippling them with a series of howls.
If left to prowl their native plane, howlers would be another blight upon Pandemonium. However, howlers could be found in most of the Lower planes, in particular those defined by chaos and evil, captured and trained by those that had learned to tame them. Quasits, abyssal orcs and succubi were known to use howlers as mounts and pack animals while larger demons used them as hunting hounds. They were just as powerful as draft horses and far more capable of traversing Pandemonium's tunnels, making them far more effective steeds. Although their abilities were less effective against outsiders, howler packs were commonly deployed in the Blood War due to their ability to neutralize the enemy for a few precious seconds.
Domesticating them was a serious ordeal requiring the howlers to have a positive disposition to their master combined with a brutal period of training, until the creatures recognized their trainer as the undisputed pack leader. Both fiends and evil mortals of sufficient strength and viciousness could train a howler pack to show complete loyalty. On the Material Plane, troglodytes, shadar-kai and drow were known to capture young howlers and train them for war. Sufficiently old howlers could not be broken and trained but would willingly ally with beings such as drow or intelligent undead in order to acquire victims, dwelling in the prisons and torture chambers and allowing only powerful riders. The greatest of howlers served death giants, liches and similar undead as watchdogs and hunters, displaying a surprising level of loyalty to such beings and faithfully laying down their lives in defense of their wicked masters.
The baying of howlers was suspected to be a language with some wizards going so far as to claim that they hid the secret nature of the multiverse within their howls. It was entirely possible said wizards were driven to madness by their howler subjects and no language could be deciphered in their wails, whether through study or magic. While incapable of speaking they could understand Abyssal.
Howlers drew sustenance from not only the fear of their victims but also their bodies. They were carnivorous scavengers that wandered Pandemonium searching for edible scraps or weak prey. They possessed both a rutting season and defined territories, howling during the former and when the latter was being contested. Howlers generally ran in death packs of their own kind ranging from 2-20 members including the bulls, females and kits. Bulls did the hunting in the pack and older members encouraged eligible young to prove themselves during the hunt.
Young howlers were known as dread hounds and were eager to taste fear, spreading out during a hunt to maximize the chance of terrifying their prey. Grown howlers were referred to as doom mastiffs, fearsome canines that carefully closed in on prey to keep them frightened for as long as possible. While normally found in Pandemonium, they crept in tunnels and abandoned dungeons when on the Material Plane. Terror incarnates were the most fearsome howlers and were said to be the progeny of a howler that had consumed the terror of an entire army, becoming living embodiments of fear in the process. Rather than lead packs of ordinary howlers, terror incarnates traveled the planes in packs of their own kin ambushing prey in order to prey upon their shock.
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Achaierai • Barghest • Canomorph (Haraknin • Shadurakul) • Hell hound • Hordling • Howler • Larva • Maelephant • Marrashi • Night hag • Nightmare • Rakshasa • Succubus • Vargouille • Yeth hound
Fiendish creature • Half-fiend (Alu-fiend • Cambion • Draegloth • Durzagon) • Tiefling (Fey'ri • Maeluth • Tanarukk)