In “The Doom That Came to Sarnath,” settlers from Sarnath destroy the ancient city of Ib.
The story places both cities in Mnar, beside a vast lake. Sarnath’s settlers discover Ib, a far older grey-stone city inhabited by a strange, greenish race descended from the Moon. The inhabitants worship Bokrug, the Great Water Lizard.
Despising Ib’s people, the settlers massacre them, destroy their city, and carry away Bokrug’s idol as a trophy. The idol vanishes overnight, and the high priest Taran-Ish dies after writing “DOOM” on the altar. A thousand years later, Ib’s supernatural vengeance destroys Sarnath at the height of its power.
A common mix-up is reversing the cities: Ib is the ancient city destroyed by Sarnath, while Sarnath is the later city doomed for that act. Lovecraft first published the tale in The Scot in June 1920, and the story belongs to his Dream Cycle.