Ghostly Prison #71
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$6.38
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Card Details
Creatures can't attack you unless their controller pays 
for each creature they control that's attacking you.
“Though the spirits' bodies were ethereal, Agnur soon learned that their blades were quite solid—and razor-sharp.”
Illustrated by Daarken
Rulings (2)
Feb 1, 2007
In the Two-Headed Giant format, you still only have to pay once per creature.
Feb 1, 2014
Unless some effect explicitly says otherwise, a creature that can't attack you can still attack a planeswalker you control.
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