Horrer Terrers

Horrorterrors are mysterious eldritch creatures that reside in the Furthest Ring. They are enormous and extremely powerful, but their motives and agenda are unknown.

While the horrorterrors did relatively little in Homestuck beyond create dreambubbles and make Rose go grimdark for a short time, they seem to be much more active in Cool and New Web Comic. Through prototyping, Rose's Momi is now the head of the Noble Circle of Horrer Terrors, and the horrer terrers themselves intervene more in the universe, taking AR for their own purposes. They were able to do this in spite of it being against the law, an impressive feat when you consider that "the law" can stop the rotation of a planet.

While Horrer Terrers are meant to be immortal and eternal, they are somehow being killed by Lord Spanish, who is more immortal and eternal.

Hierarchy
The Horrorterrors are led by the Noble Circle of Horrorterrors, an omniscient, omnipotent order of the elite few, made up of the largest and most powerful Horrorterrors. Below them are the Middling Gods, followed by the Smaller Gods. At the head of the Noble Circle is Bg'ogubglog'ybul, who became Rose Lalonde's sprite when Hecka Jef prototyped Rose's grimoire.