Dark Spirit
From Multiversal Omnipedia
The Dark Spirit is the malevolent supernatural entity behind the Deadites, often manifesting as a rapidly-moving entity that pursues its prey until it is blocked in some way. When made to manifest in a physical form, it once appeared as a massive anthropomorphic demonic entity melded with the nearby forest. The Dark Spirit can be summoned and banished by speaking aloud certain spells in the Necronomicon ex Mortis.
