Im not sure the if this is a new thing, or if its a bug since ive been away along while but....
If you drop just 1 bomb on a CITY, in a 2 city zone it goes down 50% instantly, and bombing that 1 city more wont cause any damage. The 2nd city however will get damaged as normal, ie 50% damage to that city and the zone goes down to 25%.
not sure if its a bug or a new feature... but i kinda like the idea. hehe. Wish the strat system would change a bit...
