Upper_Krust
Legend
Hi Alzrius mate! 
Well the Cthulhu mythos would relate to the Far Realm (esoteric name: The Abyss*, a.k.a. The Seventh Dimension), with such beings akin to pseudonaturals (esoteric name: Zoas).
*Not to be confused with the home of Demons (which is why I use Far Realm instead of Abyss).
I have a few new pseudonaturals in the IH, namely the Cogent and The Krangar, but I'll probably reserve a major discussion on the Pseudonaturals for a second bestiary.
The first bestiary details the Angels, Intelligibles and Umbrals. In the second bestiary I'll detail the Elementarchs, Inevitables and Pseudonaturals. Then you'll have all the major dimensional races covered.
The Cthulhu Trinity (Azathoth, Shub-Niggurath and Yog-Sothoth) would probably be considered sidereals under my auspices.

Alzrius said:U_K, your using of Tsuggothia makes me wonder, what would the IH take on the Cthulhu mythos be? (I'll ask more pointed questions than this admittedly-vague one as per your answers).
Well the Cthulhu mythos would relate to the Far Realm (esoteric name: The Abyss*, a.k.a. The Seventh Dimension), with such beings akin to pseudonaturals (esoteric name: Zoas).
*Not to be confused with the home of Demons (which is why I use Far Realm instead of Abyss).
I have a few new pseudonaturals in the IH, namely the Cogent and The Krangar, but I'll probably reserve a major discussion on the Pseudonaturals for a second bestiary.
The first bestiary details the Angels, Intelligibles and Umbrals. In the second bestiary I'll detail the Elementarchs, Inevitables and Pseudonaturals. Then you'll have all the major dimensional races covered.
The Cthulhu Trinity (Azathoth, Shub-Niggurath and Yog-Sothoth) would probably be considered sidereals under my auspices.