>Do you need to quantify the effect of the great rituals as spells [...]?
Well looking at your (very good) examples, i'd say that the Big Ritual *is* a 'spell' with profound impact on the world. The fertility ritual, which gives the crop fields more Life Power as Ernalda and the Grain Sister and Barntar are worshipped and sacrificed to, is the main 'spell' which Bless Crops is merely a pale and weaker reflection of. Remember that a worship ceremony is also a heroquest.
A sidethought: what if the clan must successfully perform a Big Communal Ritual in order to get access to Rune Spells associated with the ritual? If the Fertility Ritual fails, can anybody in the clan cast Bless Crops? Or does a failed ritual weaken, but not inhibit, the power of the associated spells?
This could clarify the phenomenon of War Tribes and Peace Tribes - a war tribe doesn't bother with Fertility Rituals and instead goes for War Rituals, which means that the power of Bless Crops and such spells is severy reduced, but the power of martial spells (associated with the specific War Rituals) is increased.
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