Terror through time - a Mephisto review
Rhan-Tegoth is a sourcebook for Cthulhu Hack that revolves around the entity of the same name. Originally a sorcerer-king, he became an entity that exists throughout the ages after being captured by his enemies. This small book briefly introduces Ran-Tegoth's backstory and provides gameplay statistics for the entity. In addition, there are some ideas on how Ran-Tegoth's influence manifests and how the entity can be incorporated into a campaign. A few small game mechanics like a new special skill and two spells round things out.
While Rhan-Tegoth introduces a mythos entity and its various facets in just six pages, there remains the feeling that it would help to know the original story, as otherwise the introduction remains somewhat vague and not all references are clear.