Bogus commands can be made using exits. For example, to make a 'sit' command, one could "@open sit", then "@link sit=here" (because unlinked exits can be stolen), "@lock sit=me&!me" (impossible to be both at once, therefore always fails), and "@fail sit=You sit on the chair."; "@ofail=sits on the chair.". Since nobody can go through it, it always fails. The @fail message is displayed to the player, and the @ofail message (preceded by the player's name) to everyone else.