Overview
Spectres are the largely invisible versions of Demons. Other than their vague and blurry appearance, the behave and attack exactly as their visible counterparts. They basically seem to be Demons with a permanent partial invisibility powerup. In the Doom and Doom II manuals, they are described as “Great. Just what you needed. An invisible (nearly) monster.”
Spectres appear as “shimmering” beings, with their body slightly distorting and refracting the area seen through them, making them especially difficult to see in dark areas or against certain textures – like gray speckled walls. In Doom 64 however, inactive Spectres are actually visible as green-tinted Demons, and turn invisible once they detect the player. Once killed, the Spectre’s corpse becomes visible again. The Doom 64 manual adds to the Spectre description: “These beasts will eat your face off, did you expect a walk in the park?”
Powers & Abilities
Spectres behave exactly like Demons and so while they do not have a ranged attack, they have a huge advantage over many of their demonic counterparts: speed. They can outrun many of the other adversaries in Doom, closing distances very quickly, often running towards the player in a zig-zag pattern – making it harder to hit – and helping to corner the player. Their attacks do a rather minimal amount of damage, but the frenzied pace at which they do it more than makes up for it.
Since Spectres are invisible, they have a considerable added advantage over the other demons. They still make the same sounds as Demons though, which can help give away their position. When shot at, they also bleed just like any monster, which makes it evident when they are hit.