I've been writing (and rewriting!) an introductory dungeon adventure based on the maps from Paizo's Crypt of the Everflame. As an introductory adventure I am trying to include as many of the classic D&D monsters and tropes as possible.
Originally, I was going to have the final encounter - as depicted on the cover of Crypt of the Everflame - be against some sort of custom undead warlord. That basic idea then led me to start thinking about death knights and how, despite purchasing 1E's Fiend Folio in 1982, I have never actually used one in a game despite them being, in many ways, a classic D&D monster.
As I have mentioned on this blog before, I prefer to change the level of 4E monsters to match their 1E hit dice. And, if I want a lower level version of a particular monster, I can keep the same XP value and reduce its level by 4 to make an elite, or reduce its level by 8 or 9 to make a solo. Death knights had 9 hit dice in 1E. Using my "formula" this would have resulted in a level 1 solo but I decided on a level 2 solo soldier simply because the PCs will be level 2 by that point and level 2 seems like a more appropriate challenge.
Haldroun Duskmantle's story is covered in the introduction to the adventure I mentioned I am writing but his stat block is really just a de-levelled version of Lord Soth's with a couple of custom touches of my own. I rather like the idea of a level 2 monster armed with a fireball, a wall of ice, and a power word power he can use up to three times in an encounter: I will definitely playtest Duskmantle before I unleash him on the PCs!
Let's see if he survives playtesting....