COS Gamers - house rules for World at War NUMBER OF STACKS There is no limit to the number of stacks of a certain unit. PARATROOPERS Paratroopers attack on a 2 and defend on a 2 regardless of whether they are being used in normal land combat (i.e., as "infantry" or in a paradrop. Paratroopers defending the Island of Japan or Britain defend on a 3 like infantry. No more than four paratroops per Major Power may exist on the map board at any one time. MULTI-NATIONAL FORCES An Allied unit may reside in a vacant Russian controlled area as long as Russia is no longer neutral and is at war with the Axis.