Lost Soul/Doom 64

Background
The Lost Souls of Doom 64 are resurrected carcasses of those from Doom 1, resurrected by the Mother Demon. 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, their 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 does not trail behind the Lost Soul as it charges.

They first appear in MAP04: Holding Area.

Tactical Analysis
Compared to their counterparts in earlier titles, the Doom 64 Lost Souls are much more aggressive and deadly, but also more fragile. 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 defensively 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 the 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 only recommended for sneak attacks, as the long preparation time for a rocket and faster Lost Soul charge often means that the rocket will explode against a target that's already in your face.