What's the best way to beat the hag?

Like the title says, I'm in a HM, and my last one ended when the hag wiped the floor with my team, so now I'm very cautious.

I'm all the way down her lair, but haven't started the fight yet. I was thinking sneaking in, get as many hits as I can before she spreads, and then use magic missile to reduce the number of hags

I protected everyone with poison protection, but not sure if it will be enough, especially if she use the spell Hold Humanoid (she paralysed everyone like that in my previous run and destroyed me)

Any ideas/advices? Thanks!

EDIT: thanks everyone for your advices and experiences, I really appreciate it! I'm already level 6, I have the sussur weapon and only one caster, which I will use as reserve. I'll blow her up to bits!