Btw, if you think of "likely" tactics he'll use, jot them down... ussually what I do with NPC's is write down what buffs they'll use before combat and what they are likely to do during combat...
I ussually end up with something like this:
r-4: drinks potion of heroism
r-3: activates boots of speed and drinks potion of invisibility
r-2: hides in shadows and approaches party
r-1: continues to approach party and positions self in a tactical spot.
-Roll initiative
r-1: Attacks caster with so and so...
r-2: if caster dead, then tumbles to... etc..
Anyway, I'll take care of the above, but if you just think of some nasty tactics while you're writing him up, jot them down

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