Two ways to it, actually (both via Honesty).
A lot of even veteran players don't seem to know that the "Wisp" Dungeon and the "Cyclops" Dungeon are actually opposite ends of the same dungeon system.
A. Wisp Side.
Go in, go through the peaceful wisp dungeon, then downstairs. The C-shaped corridor will take you to the middle level, with evil mages, evil mage lords, undead and dark wisps. There is usually 1-2 dark wisps as you enter this direction. The Northern corner of the dungeon has the stairs up to next level (see B.)
B. Cyclops Side.
Go through the cavern with Cyclops, Titans & Ettins, between Honesty and the Juka, and enter the dungeon at the far end of the cave. Run through this dungeon, down the corridor (ignoring the additional repond spawn and the undead). When the corridor ends in a "T", go right (left takes you to the room with the Balron). At the end of this hall is the staircase down. Go through this C-Shaped corridor to the steps down. This will put you at the point (stairs up) at the end of A. above.
Next to the stairs, is a room that spawns several mage lords and dark wisps. Despite always being paragons (in terms of dropping chests), they STILL can spawn as paragons over and above their normal state, and are a royal PITA to kill as Paragons. However, that is the best room to farm them, though farming them is a lot less productive now, than before the Bag of Sending nerf.
Note that it is best for negative-Karma types to go through via the Cyclops side, as the Wisps on the other end will Aggro on them. Also, one can use the two connector "C" corridors (which effectively act like dungeon entrances and the monsters can't cross) as aid stations and places to go if you have to rez others or self-rez.
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