Destruction Spawn

Destruction Spawn were demons spawned from the Worldstone shards gathered by a hero/group of heroes, formed when they attempted to destroy the shards with Deckard Cain.

In-game
Destruction Spawn appear in the "Fragments of the Past" quest in Diablo Immortal. They are small and weak, but numerous.

Trivia

 * In form and function, Destruction Spawn are very similar to Shadow Vermin. However, from an in-universe standpoint, they appear to be separate demons.