Presence of the Old God

There is a kind of maw at the bottom of the water in the center of the Weeping Quarry - a Saronite mine - which moves and seems to be alive. Perhaps one of the "thousand maws" of the Old God Yogg-Saron or a different Old God. It looks similar to and shares the model with C'Thun. It is possible to swim into the mouth and past it. The mouth seems to disappear with only the corners remaining.