Lost Soul/Doom

"Dumb. Tough. Flies. On fire. 'Nuff said."

- Doom II instruction manual

The Lost Soul is a monster that was first introduced in Doom's second episode, The Shores of Hell.

Physical appearance
The Lost Soul is a flaming, flying skull with two horns, orange eyes with yellow dots for pupils, and very sharp teeth.

Combat characteristics
Unlike other monsters, Lost Souls do not make any sounds when alerted. They are often found in swarms, silently floating at a leisurely pace. When spotting the player, they attack by launching themselves towards their target at high speed with a hissing breath sound, often the first audible warning of their presence. If they miss, they will continue careening through the air until they hit a wall or other object. Interestingly, Lost Souls will stop when they cross an object in their charge path, such as a shotgun or a medikit, which stops them as if the objects were a wall.

In Doom II, Lost Souls are usually generated by a monster called the Pain Elemental, although on occasions, players can also find Lost Souls when the Pain Elemental is not present.

Upon death, Lost Souls simply explode before vanishing, making it one of the few monsters (alongside the Pain Elemental) to not leave any corpse or remains behind.

Tactical analysis
Lost Souls are arguably one of the most frustrating enemies in the game. Their ability to quickly close in to attack, as well as the lack of audio cues they make when alerted can sometimes catch players off-guard.

Fortunately, as Lost Souls only possess a small bit of health, they can easily be taken down with any form of weaponry. Their high pain chance can also be utilized by the player, as shooting them in their charge state will disrupt their attack. Few shots from the chaingun will usually cause a charging Lost Soul to be helplessly pushed back, leaving it vulnerable in the process.

The introduction of the Pain Elemental in Doom II has made Lost Souls become much more problematic. As these monsters can now utilize Lost Souls as their own projectile attack, it is likely to increase a swarm of Lost Souls within a short time if not dealt with right away. On the other hand, players are also given a new weapon, the super shotgun, in which one shot will obliterate 2-3 Lost Souls at point blank range. Players however, should prioritize first on dealing with the Pain Elemental, to ensure that it does not continue producing more Lost Souls in the vicinity.

Lost Souls are generally unreliable within monster infighting. The low damage they deliver, as well as the high pain chance they have, would generally cause them to perish quickly by other monsters. They will also resort to attacking their own kind, if caught in the crossfire. One unique characteristic of the monster type is that after they attack, they do not retain their target, and instead pursue the player, unless hurt by their previous target. This makes them somewhat unpredictable when a player provokes and attempts to sustain monster infighting.

Pre-release version
In the available pre-release versions of Doom, Lost Souls are grey, non-flaming and use a "psychic" attack, facing the victim and flashing for a moment, delivering a hitscan attack at the player. These early Lost Souls leave behind a pile of floating bones. The invulnerability powerup has a face similar to that of these early Lost Souls.

There exists a thing type in the final version of the game, named MT_MISC65 (called "Dead Lost Soul" in DeHackEd), which produces the last few death frames of the Lost Soul. This dead Lost Soul was evidently left over from earlier versions of the game where the monster did leave a corpse, such as in the press release beta. This thing would have served the same function as the other decorative corpses (the Imp and the Zombieman corpses, for example). Regardless, it is not possible for an Arch-vile to resurrect a Lost Soul even if it is crushed while it dies (which leaves a puddle of blood as its corpse), as it does not have a raise state.

Data



 * 1) This table assumes that all calls to P_Random for damage, pain chance, and blood splats are consecutive. In real play, this is never the case: counterattacks and AI pathfinding must be handled, and of course the map may contain additional moving monsters and other randomized phenomena (such as flickering lights). Any resulting errors are probably toward the single-shot average, as they introduce noise into the correlation between the indices of "consecutive" calls.
 * 2) Assumes that direct hits are possible, which does not occur in any stock map.

Appearance statistics
In classic Doom, the Lost Soul is first encountered on these maps:

The IWADs contain the following numbers of Lost Souls: