Talk:The Black Pits/@comment-2601:602:8480:3343:1C03:9EE7:2D28:F22F-20191106030211/@comment-67.183.86.95-20191206021541

Managed to figure this out, with some trial and error.

This fight consists of 6 undead archers (who have a high rate of fire, seemingly never miss, and do acid damage on top of arrow damage), plus 2 undead Shadows (melee attacks, allegedly drain strength, nearly invisible so presumably they have a good AC). Being undead, all are immune to sleep, hold, slow, and fear, so no crowd-control spells. They seem to be affected by Fireball, Melf's Acid Arrow, Larloch's Minor Drain, and Magic Missile -- but only Fireball does significant damage, the rest are very small. Magic weapons are also required, so two characters used longbows with +1 arrows, and two others had +1 melee weapons (one longsword, one warhammer), all using weapons with which they are proficient. The last two characters are casters, so they had no weapons, only the spells mentioned above. My cleric was fully loaded with every healing spell he can learn, plus Chant. Turning Undead does not have any effect on any of them -- presumably Shadows are high-level, and the archers are too far away (or also too high a level).

Because they use acid arrows, I tried buying each character a Scroll of Protection from Acid, which were in effect, but it only reduces acid damage, so the damage is still significant -- not worth the cost, and ultimately not necessary. I replayed without these, and did just as well.

I also considered Wands of Fire (too expensive), Potions of Healing (minimal healing, and slow -- while pausing to drink one, often more damage is taken than is healed), Oils of Speed (expensive, and just speeds up ineffective attacks), and Scrolls of Protection from Undead (only affects melee, not ranged, so no help vs. the archers).

The key: Three Potions of Explosions. Pricey, but anyone can use them, and (literally) plenty of bang for the buck.

When the fight opened, I had my cleric start casting Chant, while one caster used Fireball, and three fighters threw Potions of explosions, two attacking each side. The remaining caster used Melf's Acid Arrow, since it's the most effective thing she had. The four big booms did enough damage, including killing one of the Shadows, that my party was able to survive the rest of the fight and bring down the Night Knives archers and the remaining Shadow.

I'm not sure whether the Chant really made any difference. And since my cleric was Chanting and Healing throughout the fight, he never used his +1 warhammer, so that was probably an unncessary expense, but it'll probably be useful later.