That was the most fun I've had with this game in recent memory. The priest felt like a sensible choice for the +100% undead damage trait, as well as the increased health to synergize with Binlor resist stacking.
Pretty standard Namtar's Lair fare - binlor prep, most of my exploration used to acquire max magic resist. The Paan Labyrinth subdungeon was an amazing find; lots of walls to crush for binlor piety without wasting the ones upstairs (as those could then be used for boons/knockback), as well as a hefty chunk of blackspace to fuel endiswal (imps didn't matter at this stage of the game since you're pretty much only after MP when you're on heavy Binlor duty anyway). Once I had what I wanted from Binlor I chose to park at the Earthmother due to a lack of better options - despite having no means of generating piety for her besides the stone sigil. I grabbed entanglement to get more value out of my popcorn as well as a couple of vine forms to make the early levels even more of a smooth sailing.
Thanks to some adequately leveled frost trolls, max magic resists, some sensible regen-fighting using Whurrgarbl and the godsend that is Getindare, getting to an appropriate level to take on Namtar was a cinch. The RNG gods also decided to bless me with Wheytwut, which allowed me to place Namtar in front of a neat line of walls to punch him into. As I had his first form down about halfway I was beginning to worry about whether my resources would carry me through the rest of the run - until I realized I realized that I wasn't a monk (as I had pretty much played as I would a monk, regen-fighting and all). Somehow I had forgotten about the 100% potion recovery trait in the middle of the run - so that came as a very pleasant revelation mid-bossfight.
I grabbed the witchalok pendant as well as the crystal ball before heading downstairs, and made short work of the first vampire form. The second one, however, was looking like trouble, 180 attack when in berserk mode and all, especially since I had gotten rid of Getindare to make room for the corpse... The witchalok pendant saved me here, as I had to resort to fireballing the imps to build up physical resists to tank the hits. The two last forms were, as they usually are, nothing to worry about.
All in all a very satisfying run. If you're struggling with VT Namtar's - give the good ol' priest a shot.