I would think it would be very difficult and very long if possible, with six level 1's even if all are fully twinked out for a number of reasons.
That boss was a real challenge for a group of 6 high-40's to level 50ish characters, the one time I did it years ago. Though it was before the defiant era, and most of us in the group were poorly geared, relative to what a character today in easily obtainable defiant gear's stats would be at.
Imho, the level 1's may find it hard and too rare to get a melee shot to land on Lord Nagafen while when he casts the AE fear it should certainly land on the level 1's and the AE dispel with the direct damage effect would take a noticeable chunk out of those level 1's engaged in melee or any level 1 castor/priest in the group that are hit. Meanwhile the level 1's will get virtually none of their detrimental damage spells to land on Lord Nagafen because of their extreme level handicap vs Lord Nagafen's level. Maybe a twinked-pet strong group with hi level Mage gear and weapons on the pets could do it the easiest imo.
I'd think it would be extremely long if possible or not possible with level 1 group other than a, hi level mage twinked-pet heavy group , but then there are the probable adds which can make the situation worse.
I may be wrong, but Good Luck and Enjoy...and please let us know whether victorious or not ! That would be some story to tell and hear Edited, Mar 24th 2015 5:58pm by hexeez