Try # 3. Changes are to make the ONCE apply to the rule number, and
to use X as a wild-card seed:
Within one week after an existing rule is mutated (its power is
changed), a Farmer CAN once Harvest the ID number of that rule, and
harvest any other crop and specify the Seed of a Digit Ranch e owns.
As soon as possible after doing so the SoA CAN and SHALL destroy a
Digit Ranch of the specified Seed in that Farmer's possession, and
create in that Farmer's possession a Digit Ranch with the Seed
specified by the additional crop (if the additional crop was X, the
Farmer when harvesting the crop MUST specify a crop other than X as
the Seed).
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Benjamin Schultz KE3OM
OscarMeyr