rarity is basically based off of how many active users a country has. if a country only has 3 users then that would be really rare that you would be able to get that flag. if you got a flag with italy with over 1,000 active users then that would not be very impressive.That's basically what I'm doing.Bang out the rare flags now and then cruise in on the big countries.9 of my 31 flags are from nations with 25 or less users, 6 of those from nations of 10 or less
rarity is basically based off of how many active users a country has. if a country only has 3 users then that would be really rare that you would be able to get that flag. if you got a flag with italy with over 1,000 active users then that would not be very impressive.
That is definetely the best thing to do, but one must consider also that countries that have less than 10 users today might have much much more in the future, so it would be far easier to get those flags later on...