The best build in feudalism 2:
Start as a southern desert warrior,
make sure you have the 2 aura skills (unholy breath and balance of force)
and the katar skills

Use your skill points to first build up DEX until 100
build your strength over the levels and get it to about 85-95
use the rest to upgrade CON and SPR to about 65-75 
upgrade katar to 80 points,
use the rest however you wish.

as your DEX goes up, get better katars from better cities,
Until level 10, get money by doing rouge-dealing and then 
start conquering the 1,2,3 & 4 star town (with an army) of the great trade republic 
and the black horde land, then the order of the holy cross.

by this time, you should be lvl 30 maybe, if not just do the
same with the forest land, by the way, on your skills table you 
should have lvl 5 on all katar skills, balance of force and unholy breath.
the passive skills aren't 100% necessary, but if you want them
you can upgrade them with the spare points. 

When you have 100 DEX, get the black shogun armor 
and mask from Nagoya, the Assassins might from Tiflis
which you may want to refine and enchant with a rune at the forge

To be more powerful than anyone, you need to, at the beginning of battle,
use unholy breath and balance of force and meteor strike and 
just attack.

With this build, a high majority or all of your enemies will kill each other, 
be poisoned or immediately die, however you may need to kill a few
of the enemies, but i guarantee 99.9% you will win any battle.