nomic/immutable_rules/109_Transmutation.md

Rule-changes that transmute immutable rules into mutable rules may be adopted if and only if the vote is unanimous among the eligible voters. Transmutation shall not be implied, but must be stated explicitly in a proposal to take effect.

If the game is being played over git, a simple file move to or from the immutable_rules/ or mutable_rules/ directories shall satisfy this rule.