The Atlach-Nacha was a creature with the body of an arachnid but with the eyes of his fellow man. It was believed by TEd Carnby that the shadow-vermin at Lorwich were similar but were less powerful and different. Carnby also believed that there was hint of something once human inside it.
- Atlach-Nacha was a created that appeared The Seven Geases, which was based on the HP Lovecroft's mythos.
In the original transcript, Ted Carnby faced the creature along with some proteges. Although Carnby was triumphant, one of the proteges died and another went insane.