Nessian pit fiend
It is a more powerful version of the pit fiend and has most of the same attacks. In dNetHack the regular pit fiend's second weapon attack is replaced with a claw attack, and instead of a grabbing attack it has a spellcasting attack and a poisonous bite that reduces strength. In addition to these, the nessian pit fiend has a passive attack that deals fire damage to anyone who attacks it in melee.
Nessian pit fiends get their name from appearing, along with a number of lesser pit fiends, in Nessus, at the court of Asmodeus. A single nessian pit fiend (dubbed a "traitor pit fiend") also appears in the court of Demogorgon.
The great horns, bat-like wings,
serpentine tail, and cloven-hoofed feet are identical to
the terror of the pit. Yet, this creature towers 20 feet in
height. Accompanying the flames that lick its translucent
flesh is a darkness that ripples the surrounding air. The
blood red form is covered in muscles and the burning,
white eyes glare from a shadowy face.
[ Dicefreaks: The Gates of Hell ]
- dNetHack gehennom.des, line 2579
- dNetHack gehennom.des, line 2980