Lost Soul/Doom 3

The Lost Soul in Doom 3 is a head-sized flying demon consisting of a human face mounted on a flying rocket engine contraption. Its jaws are torn apart to allow it to open its mouth wider than a normal human could and its teeth have mutated to long, pointy, needle-like teeth.

They hover through the air at average speed, and attack by abruptly rocketing in a straight line towards the player at high speed and ramming into them, similar to the classic Lost Souls. Unlike the classic Lost Souls, Doom 3 Lost Souls can cover a larger area and can change course if necessary. The Lost Soul is usually found in packs with other Lost Souls (which was often the case in the classic Doom games as well). The Lost Souls can be problematic opponents if the player does not manage to kill them quickly. They first appear in the EnPro facility.

The first appearance of a Lost Soul occurs in a grotesque cutscene with Theresa Chasar, one of the few female UAC employees. When the marine approaches, she whispers "help me", then her facial skin starts to shrivel inwards while acquiring a horrible pale color, and a Lost Soul bursts out of her head, ripping out her spinal cord in the process.

Doom 3's version of the Lost Soul is very weak. It can be taken down by a single punch if necessary, although it takes two pistol bullets to kill.

The Machinegun or the Plasma Gun are the most efficient weapons for taking down Lost Souls, thanks to their high accuracy and rapid rate of fire.

The Resurrection of Evil expansion pack replaced the Lost Souls with a new monster called the Forgotten One, which bears a closer resemblance to the classic Lost Soul.