Fate of Cthulhu is a standalone horror TTRPG published by Evil Hat Productions in 2020, powered by the Fate Core System.
Players become one-way travelers returned from a dark, Mythos-ruined future who, with allies in the present, work to stop the apocalypse the Great Old Ones would bring. "The stars are right for Great Cthulhu’s return; it’s up to you to make them wrong again."
It features a Corruption mechanic that tracks how close the heroes are coming to the very monsters they fight, translating cosmic horror’s paradox — the more you fight it, the more you resemble it — into rules.