In order to deal with this, once someone is in the cauldron it has substantially less HP and no PROT so one or two good hits will dump someone out of the pot.

That being said, once someone is thrown in the pot, your formation is altered in kind with everyone pulled forward to compensate for the loss of space, and subsequently pushed back once they are released. Once a person in the pot is at Death's Door, they will be dumped from the pot and placed in the front row, which can be extremely hazardous if your healers or someone very specific (ex: Abomination, Rank 2 Vestal, Incision PD) were in the pot to begin with. Into the Pot is a physical attack with a high hit rate, and once a hero is in the pot they will take roughly 9% of their max HP in damage every action, so you have roughly 10 actions, including the Hag's, to free a victim. The Hag's first and most damaging attack is Into the Pot (Labeled as Behold my Gimmick in the vid), a physical attack that will choose a hero to throw into her cauldron. Also, if you run from the Hag while a hero is in the pot, the hero is killed as a result since no one saved their life.

One major thing to note: The Hag and her pot cannot be moved since they each have maximum move resistance on every difficulty, and when the pot isn't filled it has huge HP values along with 100% prot so you aren't removing its gimmick by any normal means. By reducing your team's damage output by one body, this makes the fight a delicate balance of keeping heroes alive while actually damaging the boss itself. The Hag is your big lesson in understanding the concept of Action Economy, since unlike the Necromancer she gets two actions per turn, and her gimmick specifically reduces your actions by one whilst damaging said removed action. The Hag is the first boss you will encounter in the Weald, and its honestly the hardest fight out of all the normal bosses from my viewpoint. There may be inaccuracies, they will be addressed once pointed out. Hello I'm writing this at midnight in a caffeine-induced state.

Darkest dungeon hag cauldron