Lost Soul/Doom 64

Background
The Lost Souls of Doom 64 are resurrected carcasses of those from Doom 1, resurrected by the Mother of All Demons. They are made from systematically altered dead carnage remade back into corrupted living tissue. The mutations were devastating. The demons have returned stronger and more vicious than before.

It's Tough. It Flies. It's On Fire. These Lost Souls seem to warp into existence from another dimension. In some areas, there seems to be no end to them and their fiery attacks.

These variations of the Lost Souls look somewhat different; in their new mutations they have become slightly transparent, the skull faces are more demonic in appearance, and there is fire only on the top of their skulls (the fire is also transparent). The fire atop their heads do not trail behind the lost soul as it charges toward the player

Compared to their counterparts in earlier titles, the Doom 64 lost souls are much more aggressive and deadly. Their charging speed is much faster than before, they will repeatedly attack a player mercilessly should it get close enough, and swarms of lost souls can tear a player to pieces in mere seconds. That said, they are weaker defensely than earlier incarnations (they can be killed with a single point blank shotgun blast as opposed to needing two in earlier games; a trait held over from he PS1 port), so fast firing weapons like the chaingun and plasma gun make very short work of any hordes of lost souls you are bound to come across. The rocket launcher is NOT AT ALL RECOMMENDED, as a lost soul could charge at you as up you fire it, causing the rocket to explode in your face.

They first appear in MAP04: Holding Area

Info
It is also physically weaker than their PC counterparts and can be felled with a single shotgun blast (not unlike the variants found in the PlayStation and Saturn ports).

The Lost Souls in Doom 2016 (react more closely to these kind but explode on contact with the player)