Lord Loren Soth said:
what happen when a noble attack a neutral city and the city have a partial victory(the baron inflicted 200 casualties + 1 victory for his special ability while the neutral city played -100 casualties + 2 victory cards)?
It would depend on the city being attacked.
If it's a (shield) 2 city: It recieves 1 breach marker because you dealt 100 casualties on it. But you are killed* because the city had 1 more victory than you.
*meaning you return to "base".
I don't have the rulebook in front of me though, but victories are more important than casualties in WK. Unless a city dealt you 200 casualties, and you only have 200 troops with the noble. You could have 2 victories and still lose. But if you only had 1 victory and 1 prevent 100 damage, you would win. Only having to put a -100 token on the unit that was damaged (during muster forces you can pay 2 crowns and remove the -100 token from the unit.)
Hope some of this was helpful.