The rule could be anything, as funny or as serious as you want. The universe will progress in a similar way that it has up until this point, unless your changed rule prevented it from doing so.

Some examples might be:

  • The invention of currency is not allowed.
  • Iron is slightly less stable.
  • The Ancient Greeks are able to cultivate Silphium, which does not go extinct now.
  • HipsterTenZero@dormi.zone
    3·
    22 days ago

    I will hard reset the universe. The new rule is that any sapient lifeform has the power to reset the universe.

    Welcome to the crabbiest of crab bucket universes.