Great Old Ones

Great Old Ones are a pantheon of demonic extraterrestrial gods from the works of H.P. Lovecraft that are more known amongst mortals than the Outer Gods but are infinitely less powerful.

Regardless of this fact the Great Old Ones are completely invincible in comparision to humanity and their alien nature is so utterly bizarre that it inspires madness in all who gaze upon them.

Cataclysmic but not necessarily malevolent the Great Old Ones have the power to end the world on a whim but don't actively seek the destruction of humanity, perhaps it is due to their vast power - to a Great Old One humanity just isn't worth the trouble of extermination.

Of course on the other hand a Great Old One could simply choose to destroy entire civilisations for no other reason than it felt like it, a Great Old One has no care if its actions cause the deaths of thousands and if a Great Old One should become hungry or bored it sees no wrong in randomly torturing or devouring innocents.

According to Lovecraft himself the Great Old Ones were meant to be amoral rather than malicious, in keeping with his belief that the universe itself was alien and uncaring - this by no means lessens their danger, arguably it only serves to increase it.