Bio: The Soul-Beast was created by Doctor Glitternight from the dark aspect of Topaz's soul, which he stole from her when she sought him out to help her restore her fading powers. The Soul-Beast took on two forms, each could possibly be described as separate entities (and Doctor Glitternight did refer to them as his "first born" and "second born"), but since they were both formed from Topaz's soul, they're almost essentially the same being. Both creatures were killed by Werewolf by Night. The first after a fall from a cliffside where the beast landed first and the werewolf landed on top of it, and the second after the werewolf yanked on the beast's eye stems, causing it to run blind, trip over a rock and impale itself on a large rock formation.
Notes: Although not officially named within the story itself, the cover of Werewolf by Night (1972) #27 refers to the creature as the Soul-Beast.