Frustrated with the endgame. If I carry out the second part of the endgame physically, as I presume I am supposed to do, then doesn’t the final move obliterate the penultimate letter? And the final letter, to answer the question correctly, must be present. I’ve absolutely no idea what I should be putting in the barred-off cell, which is away from the field of play. I can see three distinct possibilities, none of them wholly satisfactory. Does this puzzle refer to the concept or an actual instance?