There are a few different way and strategy to capturing a lvl 8 & 10 npcs.
But this is how I do it...Capturing Lvl 10 Npcs City:
Require about 200k archers, 200k warrior,
a lvl 10 rally spot and lvl 9 feasting hall
( Most of your research tech should be at lvl 9+ like archery, military tradition ects... )
Note: a lvl 10 compass can be a problem so i suggest keeping compass tech at level 9I. 1st Attack
with 3 waves of 5k warriors within less than a minute before the Spearhead hit.
( if you dont have a lvl 100 hero then this will help lessen your archers lost )II. Spearhead:
* Use Lvl 80+ Hero,
* 1k warrior, 1k pike, 1k sword, 100 scout, 100 worker & 96,800 Archers
Note: For lvl 10 compass tech ... wait til you have a lvl 90+ Hero and use this layer :
* 2k worker, 2k warrior, 2k pike, 2k sword, 2k scout, 90k archers III. After Spearhead Hit
* Attack city loyalty down with 5 wave of 30k archer & 30k warrior within every 3 minute.
* Then keep attacking it with 20k archer & 20k warrior within every 3 minute.
( if necessary you can also use 10k archers & 10k warriors within every 3 minute )
Optional: For quick loyalty attacks but higher archers lost...
just use 30k or 15k archers and no warriors to attack city loyalty down within every 3 minute.Side Note:
* You can scout the lvl 10 npcs for a low level hero while waiting for the Spearhead to hit it.
* Sometime even when the city loyalty hit at zero,
you might have to attack it a few more time before it let you capture it.
* It should take less than 40 hit to capture the city.
* Make sure all Hero in feasting hall is full of energy.As for capturing lvl 8 Npcs City
It's pretty much the same method...
* except Hero can be lvl 70+
* just use spearhead and no need for 5k warrior waves attack
This is just one simple basic method for beginner...
There are of course advance method to capturing a lvl 10 npcs city in less than 10 minutes.
But i'm too lazy to write it all down
Anyway good luck and have fun capturing your lvl 8 & 10 npc city.
BASIC Lvl 10 farming with lvl 100 Hero at 290 Attack points
[ lvl 10 archery, lvl 10 HBR, and lvl 9 Compass ]