Official Talk:Carpentry
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Beware the Red Blinky!
It requires three rather than two turns of being ignored before single squares start breaking off the perimeter of holes which have not had pieces placed in them. That is, blink red, ignore, blink red, ignore, blink red with frantic music, ignore, break. -- Faulkston 15:13, 2 September 2006 (PDT)