NPC/A10/HB9

The best research you can get to without Michelangelo's scripts (or conquering a L10 town) is Archery level 10 and Horseback Riding level 9. Once you have these, farming NPC valleys (up to level 5) can be done easily with a minimum number of troops and zero losses. By this point your Logistics (Lgst) should be level 7 through 10. The table below is for heroes with attacks (Atk) of 20, 52, 73, and 105. To compile this list, I had Military tradition 10 and Iron working; if yours is lower, start off with 5% more ballistae per level per research (so if you have Military tradition 8 and Iron working 8, add 20% ballistae -- rounding up! -- to the numbers cited below).


 * Too few ballistae for level 1 will often result in a total loss of troops! So when possible, be a bit conservative. With the other city levels, you might lose a few ballistae, or lose the battle (100 round defeat) but keep the troops.
 * The above results will vary due to the defending city's hero. If there is any doubt, scout the city and if there is a hero, add to your balistae force (as a guess) 20% plus 1% times the level of the city's hero.
 * A "+" means "at least this many" -- that is, the attack linked to failed without losses.
 * A '-' means it might be possible to use fewer ballistae than reported so far.
 * A "/" followed by a number is the number of lost (destroyed) ballistae due to the battle.
 * Don't bother with Level 6. You'll lose lots of troops AND your loot will be only 133% of a Level 5 city.