Instructions
Start building ballistas. If you want to avoid high losses, you should plan on building at least 1000 ballistas to begin with. This should give you a good foundation from which to farm NPCs.
Research archery and horseback riding. You should aim to get your archery to level nine and your horseback riding to level eight. Make sure that you start by raising your archery first, however, to minimize losses.
Employ at least one hero with high attack. Generally you want a hero with 60 attribute points plus one point for each level your hero he has in attack. For instance, if your hero is level seven, you want his attack to be no less than 67.
Deploy adequate troops to prevent, or at least minimize, losses. For level one to level four NPCs send 100 ballistas for every level the NPC has as well as 100 or so transports to retrieve the loot. For level a level five NPC send between 550 and 600 ballistas. For higher levels, attack at your own risk and send no fewer than 1000 ballistas to prevent too many losses.