

The moment the number of nontoken permanents of the chosen color that player controls is less than or equal to the number of permanents of one of the other colors that player controls, Call to Arms’s second ability stops giving white creatures +1/+1 and its third ability triggers. Multicolored ones are counted for each of their colors colorless ones are ignored. The game continually counts the number of nontoken permanents of each color the chosen player controls. If Call to Arms changes controllers, it will continue to check the nontoken permanents controlled by the player chosen as it entered the battlefield, even if that player isn’t an opponent of its current controller. Call to Arms affects all white creatures, not just white creatures you control.
