What is happening:
One particular attack for the Level 45 Naiad is an AoE attack that looks like soap suds. While strong attacks are expected and a welcome addition, it does continual massive damage, dealing more than 2,000 damage in less than 2 seconds.
Which leads me to believe this is a glitch rather than an intentional design. Naiads should certainly not be stronger than dragons, and have no way to avoid the attack.
This is particularly annoying, as those Level 45 Naiads are the only way to get Enchanted Ice Skates, and the period which they are available is limited. And commonly takes defeating about 200 or so.
Unless said seasonal item is a common drop, it does not seem like a conscious balance choice.
Perhaps that AoE attack was meant to be a single massive damage amount of about 800-1000 damage, which would be a lot more reasonable and challenging.
At least compared to the other new attacks, this seems like a glitch that needs to be resolved. Due to other pressing matters, I could see that nopony would be able to get the seasonal item this year.
Also, the other arcing spray attack has a minor glitch where it lingers in the air.
These glitches were observed on v2018.10.1 and a Linux 64 bit system.
(This is not a frustration about not getting said item - I have it on another character, and it was rather difficult even at a high level. But after attempting to get it on another, there was a stark difference.)