As Lurebound Scarecrow enters the battlefield, choose a color. When you control no permanents of the chosen color, sacrifice Lurebound Scarecrow.
It's a fool's race to run if all is lost if it be won.
Official Rulings for Lurebound Scarecrow
5/1/2008 : If you control a Lurebound Scarecrow but no color was chosen for it (perhaps because your Cemetery Puca turned into a Lurebound Scarecrow), the trigger condition will have an undefined value in it. It'll never trigger, so you won't have to sacrifice the Scarecrow.
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