Beholder

The Beholder is a Pain Elemental variant in Doom RPG and Doom II RPG. When killed, the Beholder explodes, releasing two Phantoms.

Etymology
"Beholder" is a name of the Dungeons and Dragons monster appearing as a floating head with a cyclopic eyeball and fang-filled mouth, hence the said Doom RPG monster's design.

Its name is also a term describing a person who sees/observes someone or something. It could reference the phrase "Beauty is in the eye of the beholder", which isn't entirely true for this guy.