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Thus ends this little war.
 
The developing list of their rules:
 
Rules of Engagement
 
Rule 1: It should never be the intention any prank to cause harm, be it physical, mental or emotional.
 
Rule 2: Pranks must occur in a back and forth manner. One prank, then rebuttal.
 
Rule 3: If one sister is under too much duress to the point of it affecting her health or ability to work, it is the obligation of the other to end the prank war if the stressed sister refuses to give up. In this event, the war is a draw.
 
Rule 4: No involvement of other ponies is allowed, even indirectly. For exceptions, see Amendment 1.
 
Rule 5: Pranks may continue until one sister admits defeat or any other loss condition is met.
 
Rule 6: Once the pranks escalate to being publicly visible (as in the general public), one rebuttal is allowed, then the prank war must cease. In this event, the sister with the better of those two pranks wins. An impartial moderator both sisters agree on may be called in if necessary.
 
Rule 7: If over 50 bits worth of collateral damage is caused, the sister responsible must pay the damages cost and automatically loses.
 
Rule 8: The losing sister must surrender one months worth of sweets to the victor.
 
Amendment 1: An exception may be made if a pony requests to join. In this event, the other sister must be notified and be allowed to bring in an extra for her own side. If any sister has a significant other, that pony may not be recruited against her.