Thought I might be able to tackle something easy after the drow matron mother, but no—you guys want me to look at the nagpa, another monster with eleventy billion spells. (OK, it’s got 26. That’s still a lot.)
It’s not like you’ll even find nagpas running around all over the place. According to Mordenkainen’s Tome of Foes, there are only 13 of them—a coterie of conniving wizards cursed by the Raven Queen and turned into skulking vulture-people scavenging the remnants of lost civilizations for scraps of arcane lore.
Unsurprisingly, nagpas’ ability contour is that of a long-range spellcaster, with extraordinary Intelligence and Charisma, exceptional Wisdom and very high Dexterity. They carry staves, which they somehow are able to use as finesse weapons and deal two dice of damage with, but melee engagement really isn’t their style. If they do get into melee, they want to get back out of it quickly.
They have proficiency in all the mental saving throws, but their Dexterity and Constitution save modifiers are unremarkable. Thus, they don’t have a lot to fear from bards, whose spells tend to emphasize enchantment, illusion and crowd control; but casters who sling damaging evocation, transmutation and necromancy spells pose a threat that they need to neutralize quickly. Taking out these foes is even more important to them than taking out melee fighters.