I know maybe ONE way that doesn't make you win, but it impairs the enemy so they can't build an army of speartons. What you do is immediately send out a swordwrath and kill everyone that you can (mainly miners don't go for a spearton. thats suicide), this will help stop them from making speartons. But this still hasn't helped that much.
well you can always look at the stickpage strategy guide. the thing is that you have to get out a lot of miners and when you make your first sword/clubman, take control of it and attack the enemy. why you should take control of it is because the unit you control gets higher attack and defense. Also it is useful for more strategic play. You can make our unit run around enemy forces and dodge attack, arrows, spears and other things, the AI can't. Also, the AI will go straight for the monument, if you play it right,you will be able to pick off some miners before they escape, especially if you are able to get out an archer and pick off the computer's defense and go for the miners. I suggest doing the club/swordman harasses until you can get out an archer, when you can pick them off from a distance and they wont back off or try to kill you. hope this helped!