I just soloed her tonight (60 rogue). I attempted this several times prior to hitting 60, and I can tell you right now that without a ton of shadow and fire resist, she will "WTFPWN" you, as they say in the vernacular.

I pulled it off as a NON-EPIC Cold Blood/Preparation spec rogue (so, 24/2/25) with around 1200 HP to spare. This was an expensive project, and I also had help from engineering trinket pets. Kids, don't try this at home. Or, at least if you're going to, read the following.

This fight took me a buttload of potions. I brought along an Elixir of the Mongoose, two Greater Shadow Protection Potions (one for before and one for after killing the imp), one Greater Fire Protection Potion, one Gift of Arthas, the obligatory stack of Major Healing Potions, and I managed to get a Major Healthstone beforehand, too. Quite the shopping list, right?

First off, I opened with a distract and went pure DPS on the imp. This means Ambush. Lethtendris hits freaking HARD, so you don't want this to last long. I opened up with Ambush, hit Evasion, racked up my five combo points, Cold Blood, Eviscerate. I managed to kill him before Evasion wore off, so I Vanished right then. Lethtendris will usually have you dotted here, which will break stealth (potion or no), so you need to get out of her "comfort zone" before you vanish. If you're about 10 yards back from her wander path, it won't matter if stealth breaks while she's running back.

I actually screwed that last part up -- stealth broke and she turned around and came after me again. Preparation, vanish again... Woo hoo. For the "real" fight, I scarfed some health food for the stamina bonus. Always nice.

For Lethtendris, I opened up with a Cheap Shot and vanished. I wanted to start the fight off with five combo points... Hehe. Here's where it gets nuts. Went in again, Cheap Shot, Gnomish Battle Chicken, Mithril Mechanical Dragonling, Mechanical Yeti, Evasion. You can imagine what her HP bar looked like after that second Cold Blooded eviscerate. After my second evasion faded, she'd killed two of my pets, so I focused on interrupting her casting whenever possible. Took her down right after she nuked the yeti into oblivion... Little over 45-50 second fight.

Note: healthstones are on the same timer as thistle tea. You have been warned.

Also, Dragonbreath Chili and Instant Poison are great in this fight. So's a scroll of stamina.

Edit: When I say "non-epic," I mean blues and greens -- think I had my three BoE Tier 0 items, a Shadow Prowler's Cloak, chest and shoulders from Maraudon, and the rest were "monkey" greens. Weapon-wise, I'm pretty sure I was using a Thrash Blade mainhand (with a fiery enchant) and a Hanzo Sword offhand (also with fiery) back then.

courtesy or Allakahzam.com