Banshee are really scary monsters. Make save.
They used to be anyway. CR 4 where the wail only drops you to 0 isn't that scary.
I have to disagree. I've used banshees at low levels and been on the receiving end as well, and they are definitely scary IME. The wail alone can TPK a party that rolls badly.
A banshee to me should be the powerful undead. I get that it's still got some bite, but it's waaaay diminished from prior editions.My friend once used multiple banshees against us in a high level fight (a powerful undead and his banshee minions). He was "nice" and only used one wail a round. We managed to pull though, but it was a nail biter. Several party members went down. If he'd spammed wail in the first round while we were all grouped up, it would have almost certainly been a TPK.
And that's why it's not scary to me. The party has to roll badly. In 1e-3e, it just took a single character rolling badly. THAT was scary.
A banshee to me should be the powerful undead. I get that it's still got some bite, but it's waaaay diminished from prior editions.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.