To kill this guy you must get close to him as its his ranged attacks that is the killer. I used the attack buff and defence debuff(forgot the name but it was still lvl1 skill) I did also have the creature out at the time.
use a HP pot only when his confuse works on you, use the 'dash' attack IF IT DOES NOT BUG UP ON TERRAIN! hope to see a fix for that soon.
I doubt you will have life leech at this time (I did not) but it would help altho you would be at a high level for this part of the game.
anyway hope this helps a few ppl