From DominionStrategy Wiki
You may trash a card from your hand.
+1 Card per card the player to your right trashed on their last turn.
 Official FAQ
- You draw cards even if you did not trash a card.
- One way to keep count of the number of cards trashed is to put them on the trash sideways.
 Other Rules clarifications
- This counts the number of trashing events, not necessarily the number of actual cards trashed. For example, if the person to your right trashed a single copy of Fortress multiple times, you would get +1 Card for each trashing
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