well, I did it with a party of average level 22 and found it fairly hard, so Id advise not starting it untill your at least very near the end of SoA, if not some way into ToB
But thats just my experience, i don't know if others found it easier (I have a very badly made PC
)
)
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Nicodemus Deathslayer, Paladin and Undead Hunter of the Order of the Holy Flame