Moon dust bombs and vampire oil should work wonders. But for the actual fight - evade like hell. 
I have decided that fight is borderline impossible without any vampire prep (Obviously I had no idea they're would be one) as the whole dodge thing can work, but he just goes mental and runs around impossible to lock on to then boom hes full health again within a matter of seconds. Don't really wanna load an earlier save, but looks like i'm going to have to soon :'( First time trial and error doesn't seem to get me anywhere.Moon dust bombs and vampire oil should work wonders. But for the actual fight - evade like hell.
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Yeah as this says http://auluftwaffles.com/2015/05/20/kill-katakan-higher-vampire-in-now-or-never-in-witcher-3-wild-hunt/ Its basically impossible with average gear and being the level it says you should be on higher difficulties. Basically I need to outlevel this quest now, side quests away..!
It was hard fight, killed him without bombs or oils (didn't have them ) just rolled around, used tawny owl and axii stun when possible. Well he healed 3 times up to full hp before I took him down.
) just rolled around, used tawny owl and axii stun when possible. Well he healed 3 times up to full hp before I took him down.I got him as well, stuck some runes in my sword and basically did a dps race and drunk enhanced swallow like there was no tomorrow. Gotta say though i'm not keen on these vampires fights iv had, their slimy buggers.It was hard fight, killed him without bombs or oils (didn't have them
