AndreasHelke: All passes used on a mobile device automatically count toward this number.
FTFY. AFAIS, all passes count regardless. Thus, PC players can help to release the war but they can't help during war - quite inconsistant.
And, there's a bigger urge to buy passes during war because players shouldn't get more than one free pass per 12 hours which means only two shots in 24 hours of war.
OTOH, the "prizes" are outright ridiculous: 1 $'s worth of coins, a marginal no. of XPs (1 % of the step from L7 to L8), and an oh-so-precious Superpass for the next Event...
This is another war that ain't worth fighting!