Nightshades are high-level monsters that for once aren't outsiders or dragons. I don't recall them seeing much play, though they are interesting for being undead that lack a former living existence. They come in three flavors, ordered from stronger to weaker.
No, not this one. Nightcrawlers are undead purple worms, except they have a ton of spell-like abilities, energy drain, and some quality defensive abilities. The main issue? They've got 25 undead HD.
This means that nightcrawlers are thirteen points of BAB behind a fighter of equivalent level, which single-handedly closes the gap in melee ability between them. One shouldn't turn to their casting side either: nightcrawlers barely have anything worth mentioning at those levels. They don't even get to create undead: the best they can do is swallow people, energy drain them to death, spit out the corpses, and wait for them to become (free-willed, CR 3) ghouls.
Honestly, there's neat stuff here, but in the end I think this boils down to +0 vs. -0. For now I'll opt for the second, though perhaps the Playground's view on those matters is different.
These slightly smaller (Huge) nightshades are humanoid instead, and presumably able to handle weapons. The question is whether that's desirable: they have only +10 BAB after all, which is far too little for a creature that's already Epic.
Perhaps their special abilities will help? Crush Item is just a fancy way to destroy loot, Evil Gaze is a moderate save-or-lose, but it's paralysis based and doesn't have a great range. The SLAs are almost identical to the nightcrawler, and in fact most of this creature is. Even so, it's underwhelming for an Epic character. -0 LA.
By the way, if you want a laugh I suggest reading its suggested tactics. It spends two rounds on grabbing an weapon and crushing it, then attacks the disarmed foe rather than focusing on the enemies that are still threats.
Last of this Unholy Trinity is the nightwing, an evil bird. They have the ability to drain the enchantment bonus from items they touch, which while surprisingly useful against stuff like a +1 Flaming Vorpal Spell Storing Greatsword of Speed in the hands of an enemy pouncebarian is otherwise just another way to destroy loot.
Again, same SLAs, except one of the only useful ones (Greater Dispel Magic at-will) is now gone as well.
From an ECL 17 creature, I'm going to have to expect more. -0 LA again.
Next are nymphs, which should be less overwhelming to rate.