Horror

The Horror is an enemy encountered in The Nameless City. They make their first appearance in E3M4: Crypt of the Flesh and make appearances in several levels that follow.

Appearance
Horrors resemble red humanoids that have hollow eye sockets, elongated mouths, and skinny limbs. Parts of their extremities are webbed, giving them an appearance similar to that of a frog. Their most notable feature is their mouth, which is grossly disproportionate to their body. Horrors fly back when killed and violently curl up in a ball when they land, emitting a sound similar to bones being snapped during the process. This can be interpreted as a very brutal rigor mortis.

Tactical Analysis
While idle, Horrors will breathe heavily through their open mouths. This gives away their position to players, similarly to the Leatherneck's idle breathing. Once a player is spotted, they will gasp and start to run towards the player, flailing their arms as they do so. Their primary attack consists of spitting green projectiles (possibly acid or phlegm) in a spread similar to that of the Possessed Scarecrow. This attack is extremely high-damage up close, but the spread falls off with distance. Horrors also have a high health pool of 700hp, making them a tough enemy to beat.

Horrors are weak to stronger weapon types, such as the Super Shotgun, Hunting Rifle, and Riveter. Most of these weapons will kill a horror in two to three shots, but the Super Shotgun acquired in E3M4 is capable of dispatching them in two point-blank shots. Additionally, the Sword can be useful for reflecting a Horror's attack back at them, which can be enough to kill them in a single point-blank reflect.

Lore
Jakob states in E3M4 that "The closer they got, the more they suffered" may be a note that the Horrors are other Intruders who failed and have been brutalized into becoming a Horror.

Trivia

 * The Horror's amphibian appearance may have something to do with the protagonist's fear/dislike of frogs, as is stated in E3M7: Homecoming.
 * The idle breathing of the Horrors encountered in E3M4 can give the false illusion that the level, which has fleshy spiracles in some wall textures, is breathing.