The first Nightmare Imp encounter, found at the beginning of MAP 03: Main Engineering.
This screenshot is taken from the Doom 64 TC for technical reasons.
The Nightmare imp is a translucent blue/purple
imp which is faster than the standard imp and is the first new monster encountered in Doom 64. It hurls purple fireballs which are faster than those of the standard imp.
ID # 400 (decimal), 190 (hex)
Hit points 60
Reaction time 8
Pain chance 50 (19.53%)
22: Affects Kill
?: Rendered with Additive Translucency
Sprites & sounds
Sprite name NTRO
Alert sound DSBGSIT
Pain sound DSPOPAIN
Death sound DSBGDTH
Action sound DSBGACT
Sprite name NMBL
Sound DSFIRSHT (firing) DSFIRXPL (impact)