In the rule “The Grid”, subrule “Location”, replace “If no other Runner has this Cell in their Location at the time the message is processed, the Gridmaster sets the Location of the Runner to the requested Cell and replies with an acknowledgement of the request. Otherwise, the Gridmaster replies that the Cell is taken. ” with “The Gridmaster should then set the Location of the Runner to the requested Cell. If at least one other Runner has this Cell in their Location at the time the message is processed, the Gridmaster should also reply that the Cell is occupied.”