Obscene Fertility Rites of Shubniggurath

School transmutation [chaotic, evil]; Level 8


Casting Time 8 days (8 phases of 1 day)
Components V, S, M (as many kinds of tame and wild animals as possible are slaughtered and eaten throughout the week), F (7 Huge pillars of stone), SC (at least 100 and up to 2,000 participants, each of which must be able to survive a week-long festival of mindless orgies and ecstatic violence, and at least 10% of the participants must be non-humanoid; +1 circumstance bonus on ritual skill checks per 100), L (in the wilderness), T (begin 7 days before the Spring Equinox)
Optional Components F (the tome Cultes des Goules gives a +5 insight bonus on ritual skill checks if at least 100 Mythos ghouls participate)
Skill Checks Craft (masonry) DC 15, 1 success (diagram); Knowledge (planes) or Profession (Yog-Sothothery philosopher) DC 30, 7 successes


Range 50 miles
Diagram the focus pillars must be evenly spaced at least 30 feet apart in the shape of a “V” and kept covered in blood no less than 24 hours old for the duration of the ritual
Area 50-mile radius centered on primary caster
Duration 1 year
Saving Throw none; Spell Resistance no


This powerful ritual channels the fecundity of Shub-Niggurath to an area, which gives Shub-Niggurath influence stage 2 over the area for the duration. Crops are lusher, beasts and humanoids breed more easily and quickly, and fertility increases significantly in general. Additionally, 50% of all creatures born are mutated in some way. This may be simply be a strange appearance and a Mythos taint that grants a bonus on ritual skill checks, or as extreme as being a Mythos satyr or having the half-fiend template. Each of the ritual’s focus pillars is Huge, with hardness 8 and 600 hit points. If a pillar takes 300 or more points of damage, it is unusable for the ritual (and the ritual fails). During the ritual casting, the first time a pillar is damaged in some way, a dark young of Shub-Niggurath emerges from the woods or wilderness within 300 feet to defend it and kill any interlopers. This can occur once for each pillar.

Section 15: Copyright Notice

Sandy Petersen’s Cthulhu Mythos, © 2017, Petersen Games; Authors: Sandy Petersen, Arthur Petersen, Ian Starcher.

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