Whenever one or more creatures you control attack, each defending player divides all creatures without flying they control into a "left" pile and a "right" pile. Then, for each attacking creature you control, choose "left" or "right." That creature can't be blocked this combat except by creatures with flying and creatures in a pile with the chosen label.
![Raging River [International Collectors’ Edition] | Grognard Games](http://grognardgames.com/cdn/shop/files/7359c036-cc46-4173-80b7-b280bd8dffc1.png?v=1776162731)
