Coinchenn is a marine tentacled horror made of fish, whale, and octopus-like features. Behind the MythosEdit This entity recalls the Coinchenn, a cetacean sea monster of Celtic Mythology. This article is a stub. You can help the The H.P. Lovecraft Wiki by expanding it. Categories: Articles including information from the Expanded Cthulhu Mythos Article stubs Great Old Ones Add category Cancel Save Community content is available under CC-BY-SA unless otherwise noted.