Hit the button, then quickly retreat to the square with the north or south tunnel thingy and stay there.
×The roaches on the same side as you will stay close but not go around corner. The roaches from the other side will come at you, but since you are protected by the small alcove, it is easy.
Click here to view the secret text
×Now, the remaining two guard the alcove and don't let you come out. Enter the tunnel with the sword facing the wall (south if you are in south alcove). The rest should be easy.
