At first I misremembered the game's name as Zombie War, and I spent half an hour searching and playing very old games on Crazymonkey Games website. I still remember the last stage that I failed many times on it, eventually I got the huge machine squad and won the whole battle. End. To the campfire scene. Hah.
I dont think its the right reason for selling opium to China,but China at that time was really unsensible.In spite of this,selling opium is not justical.As a Chinese,I dont have a good mood to play the game.
Try this:buy hunter,upgrade to recruit bowman,upgrade to archer, upgrade to Elite archer,and the upgrade points(1 point per level,give the latsest build unit)all upgrade the archer's attack rate.place the archer at the southwest or southeast place,for that u can get support fire from your king.If u think u have enough money,u can but another archer,or other something,and upgrade it to the maxmiun level,then your king will never get attacked :)