How to beat the last map (To the fire in the blood)

[Crayno]

I've been enjoying this expansion so far but I've come to a point where I'm stuck pretty much.
I'm playing on normal and everythng went pretty smoothly, even a little bit too easy even but I'm planning on another playthrough on hard.
If I can beat this lasy map that is.....I can't even beat one of the Sellswords, let alone 3 ....and then the final fight which seems to be impossible.
Can you provide me with any tips? Even a cheat would be welcome to be honest.

Thanks