Barghest

Barghests are fiendish, wolf-like monsters that can shift between the Material Plane and their home on Gehenna (a lower plane). They serve as cunning, malevolent entities that devour the souls of their enemies, growing stronger with each consumed spirit.

The glowing blue orbs on the creature's body represent souls and life force it has absorbed, which is a key aspect of a Barghest's fiendish nature. The dark, almost shadowy appearance fits well with the Barghest’s ability to blend into darkness and stalk its prey.

In terms of abilities, an ancient or legendary Barghest would have access to both magical and physical attacks, including phasing between planes, using fear-based abilities, and commanding lesser fiends or shadow creatures.