A twisted humanoid, fingers replaced with dark blades

From BatWiki

Description:

A horror from the darkest nightmares stands in front of you; a demon summoned from the lowest planes of hell. It is a murderer demon, malevolent monster whose only purpose is hunt down and slay living beings. Only a very powerful wizard or evil priest could possibly control this creature - and even whilst under someone's control, there is always the risk that it breaks free from the spell and slaughters everyone in sight, making no difference between its former master and its normal prey.

Demon assassin's equipment:

Finger: Black, twisted finger-blades

Spells:

lava storm

Skills:

Missing skills

Area:

Millie's nightmare

Alignment:

Missing alignment

Race:

Missing race