Valmallos is the primordial inevitable charged with making sure that magic is difficult to cast, and requires rare and expensive spell components in order to do anything unusually cool.
Its clerics invent needlessly complicated versions of spells, try to eliminate the older simpler versions, and promulgate the public belief that if you know a simpler spellform this is a valuable secret to share only with trusted apprentices.
Valmallos locally enforces and embodies, within Creation, the transuniversal Law that says you can't have nice things; or at least, only with pains and costs.