When deploying your army, take two of the four Scavengers and put them with the general. To replace them, put two Shaklats beside the other two Scavengers. For everything else, put it in a square around the general, with him in the middle. When it starts, use a 4 card on the two Shaklats and Scavengers. On your next turn, send in a Thrall and Scavenger from the general's square. If done correctly, your enemy should go into a passing streak, doing nothing but passing. On the next hour, use a 4 and the Shaklats and Scavengers again. The enemy should send some units from the right gate to them, but should not attack. Send the Thrall and Scavenger in some more on your turn. The enemy should now start attacking the Shaklats and Scavengers. How the rest of the battle goes is up to you, but if done correctly, near the end the enemy will move toward the others when the Shaklats and Scavengers are removed. Use a Scavenger to destroy the left gate, and the opponent should get his ninth point. On the next turn, use a card which gives a used unit an order. Use it on the Scavenger near the box. You should be able to reach the box. On the final turn, the enemy should attack, but should not get the last point.
Demons! mission: Reaching the box
In the campaign mission called Demons! to reach the box, create a diversion then send a cavalry unit ahead along the perimeter of the screen. You can get the box and complete the level easier.